Viking Therapeutics Inc.

09/23/2026 | Press release | Distributed by Public on 09/23/2026 15:13

Supplemental Prospectus (Form 424B5)

Filed Pursuant to Rule 424(b)(5)

Registration No. 333-297820

The information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell, nor a solicitation of an offer to buy, the notes in any jurisdiction where the offer or sale is not permitted.

Subject to Completion, dated September 23, 2026

PRELIMINARY PROSPECTUS SUPPLEMENT

(To Prospectus dated July 29, 2026)

$

% Convertible Senior Notes due 2032

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We are offering $ aggregate principal amount of our % convertible senior notes due 2032. In addition, we have granted the underwriters an option, which is exercisable within 30 days after the date of this prospectus supplement, to purchase up to an additional $ aggregate principal amount of notes solely to cover over-allotments.

MATURITY; INTEREST

We will pay interest on the notes at an annual rate of %, payable semi-annually in arrears on April 15 and October 15 of each year, beginning on April 15, 2027. The notes will mature on October 15, 2032, unless earlier converted or redeemed or repurchased by us.

CONVERSION

Noteholders may convert their notes at their option only in the following circumstances: (1) during any calendar quarter commencing after the calendar quarter ending on December 31, 2026, if the last reported sale price per share of our common stock exceeds 130% of the conversion price for each of at least 20 trading days during the 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter; (2) during the five consecutive business days immediately after any 10 consecutive trading day period (such 10 consecutive trading day period, the “measurement period”) in which the trading price per $1,000 principal amount of notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day; (3) upon the occurrence of certain corporate events or distributions on our common stock, as described in this prospectus supplement; (4) if we call such notes for redemption; and (5) at any time from, and including, July 15, 2032 until the close of business on the second scheduled trading day immediately before the maturity date. We will settle conversions by paying or delivering, as applicable, cash, shares of our common stock or a combination of cash and shares of our common stock, at our election, based on the applicable conversion rate(s). The initial conversion rate is shares per $1,000 principal amount of notes, which represents an initial conversion price of approximately $ per share, and is subject to adjustment as described in this prospectus supplement. If a “make-whole fundamental change” (as defined in this prospectus supplement) occurs, then we will in certain circumstances increase the conversion rate for a specified period of time.

REDEMPTION AND REPURCHASE

We will have the right, at our election, to redeem all, or any portion (subject to certain limitations described in this prospectus supplement), of the notes, at any time, and from time to time on or after October 22, 2029 and on or before the 25th scheduled trading day immediately before the maturity date, at a cash redemption price equal to the principal amount of the notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date, but only if the last reported sale price per share of our common stock exceeds 130% of the conversion price on (x) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we send the related redemption notice; and (y) the trading day immediately before the date we send such notice. We refer to a redemption pursuant to the provision described in the preceding sentence as a “provisional redemption.” We will also have the right, at our election, to redeem all, but not less than all, of the notes, at a cash redemption price equal to the principal amount of the notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date, if the principal amount of the notes then outstanding is less than 15% of the aggregate principal amount of the notes issued in this offering (including any additional notes issued pursuant to any exercise of the underwriters’ option to purchase additional notes). We refer to a redemption pursuant to the provision described in the preceding sentence as a “cleanup redemption.” In addition, calling any note for provisional redemption or cleanup redemption will constitute a make-whole fundamental change with respect to that note, in which case the conversion rate applicable to the conversion of that note will be increased in certain circumstances if it is converted after it is called for such redemption.

If a “fundamental change” (as defined in this prospectus supplement) occurs, then, except as described in this prospectus supplement, noteholders may require us to repurchase their notes at a cash repurchase price equal to the principal amount of the notes to be repurchased, plus accrued and unpaid interest, if any.

RANKING

The notes will be our senior, unsecured obligations and will be equal in right of payment with our existing and future senior, unsecured indebtedness, senior in right of payment to our existing and future indebtedness that is expressly subordinated to the notes and effectively subordinated to our existing and future secured indebtedness, to the extent of the value of the collateral securing that indebtedness. The notes will be structurally subordinated to all existing and future indebtedness and other liabilities, including trade payables, and (to the extent we are not a holder thereof) preferred equity, if any, of our subsidiaries.

CONCURRENT COMMON STOCK OFFERING

Concurrently with this offering, we are offering, pursuant to a separate prospectus supplement $ of our common stock, plus up to an additional $ of our common stock that the underwriters of the concurrent common stock offering have the option to purchase from us. The completion of this offering is not contingent on the completion of the concurrent common stock offering, and the completion of the concurrent common stock offering is not contingent on the completion of this offering.

LISTING; COMMON STOCK

No public market currently exists for the notes, and we do not intend to apply to list the notes on any securities exchange or for quotation on any inter-dealer quotation system. Our common stock is listed on the Nasdaq Capital Market under the symbol “VKTX.” On September 22, 2026, the last reported sale price of our common stock was $40.85 per share.

Per Note

Total

Public offering price(1)

%

$

Underwriting discounts and commissions(2)

%

$

Proceeds, before expenses, to us

%

$

(1) Plus accrued interest, if any, from, and including, , 2026.

(2) We refer you to “Underwriting” beginning on page S-75 of this prospectus supplement for additional information regarding underwriting compensation.

An investment in the notes involves risks. See “Risk Factors” beginning on page S-12.

Neither the Securities and Exchange Commission nor any state or foreign securities commission or regulatory authority has approved or disapproved of the notes or the shares of our common stock, if any, issuable upon conversion of the notes or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying base prospectus. Any representation to the contrary is a criminal offense.

We expect to deliver the notes in book-entry form through the facilities of The Depository Trust Company on or about , 2026.

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Book-Running Managers

Morgan Stanley J.P. Morgan

Prospectus Supplement dated , 2026.

TABLE OF CONTENTS

Prospectus Supplement

Prospectus Supplement

Page

About This Prospectus Supplement

S-1

Prospectus Supplement Summary

S-2

The Offering

S-8

Risk Factors

S-12

Disclosure Regarding Forward-Looking Statements

S-20

Market and Industry Data

S-22

Use of Proceeds

S-23

Capitalization

S-24

Description of Notes

S-26

Material U.S. Federal Income Tax Considerations

S-66

The Concurrent Common Stock Offering

S-75

Underwriting

S-76

Legal Matters

S-85

Experts

S-85

Information Incorporated by Reference

S-86

Where You Can Find More Information

S-87

Prospectus

Page

About this Prospectus

1

Disclosure Regarding Forward-Looking Statements

2

Summary

4

Risk Factors

7

Use of Proceeds

8

Description of Capital Stock

9

Description of Debt Securities

13

Description of Warrants

20

Description of Rights

22

Description of Units

23

Description of Depositary Shares

24

Legal Ownership of Securities

27

Plan of Distribution

30

Legal Matters

32

Experts

32

Where You Can Find More Information

32

Important Information Incorporated by Reference

33

i

About This Prospectus Supplement

This prospectus supplement and the accompanying base prospectus are part of an “automatic shelf” registration statement on Form S-3 that we filed with the U.S. Securities and Exchange Commission, or the SEC, as a “well-known seasoned issuer” as defined in Rule 405 under the Securities Act of 1933, as amended, or the Securities Act, using a “shelf” registration process. This prospectus supplement describes the specific terms of this offering. The accompanying base prospectus, including the documents incorporated by reference therein, provides general information about us, some of which, such as the section therein titled “Plan of Distribution,” may not apply to this offering. Generally, when we refer to this prospectus supplement, we are referring to both this prospectus supplement and the accompanying base prospectus, combined.

We urge you to carefully read this prospectus supplement, the accompanying base prospectus, the documents incorporated by reference herein and therein and the additional information under the headings “Information Incorporated by Reference” and “Where You Can Find More Information” before buying any of the securities being offered under this prospectus supplement. These documents contain information you should consider when making your investment decision.

You should rely only on the information contained or incorporated by reference in this prospectus supplement and the accompanying base prospectus. We have not, and the underwriters have not, authorized anyone to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. This prospectus supplement may add, update or change information contained in the accompanying base prospectus. To the extent any information in this prospectus supplement is inconsistent with the accompanying base prospectus, you should rely on the information in this prospectus supplement. The information in this prospectus supplement will be deemed to modify or supersede the information in the accompanying base prospectus and the documents incorporated by reference therein, except for those documents incorporated by reference therein which we file with the SEC after the date of this prospectus supplement.

You should not assume that the information contained or incorporated by reference in this prospectus supplement and the accompanying base prospectus is accurate on any date subsequent to the date set forth on the front cover of this prospectus supplement and the accompanying base prospectus or on any date subsequent to the date of the document incorporated by reference, as applicable. Our business, financial condition, results of operations and prospects may have changed since those dates.

We are offering to sell, and seeking offers to buy, the securities described in this prospectus supplement only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the offering of the securities in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement must inform themselves about, and observe any restrictions relating to, the offering of the securities and the distribution of this prospectus supplement outside the United States. This prospectus supplement does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference into this prospectus supplement or the accompanying base prospectus were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

In this prospectus supplement, (i) unless otherwise indicated or required by the context, the terms “Viking,” “we,” “our,” “us” and the “Company” refer to Viking Therapeutics, Inc. and its consolidated subsidiaries and (ii) “or” is not exclusive.

S-1

Prospectus Supplement Summary

This summary contains basic information about us and this offering. This summary highlights selected information contained elsewhere in, or incorporated by reference into, this prospectus supplement and the accompanying base prospectus. This summary is not complete and may not contain all of the information that may be important to you and that you should consider before deciding whether or not to invest in our securities. For a more complete understanding of Viking and this offering, you should carefully read this prospectus supplement and the accompanying base prospectus, including the information incorporated by reference into this prospectus supplement and the accompanying base prospectus, in their entirety. Investing in our securities involves risks that are described in this prospectus supplement under the heading “Risk Factors,” under the heading “Item 1A. Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2025, our Quarterly Report on Form 10-Q for the quarter ended March 31, 2026, our Quarterly Report on Form 10-Q for the quarter ended June 30, 2026 and in our other filings with the SEC.

Overview

We are a clinical-stage biopharmaceutical company focused on the development of novel, first-in-class or best-in-class therapies for metabolic and endocrine disorders.

In January 2022, we announced the initiation of a Phase 1 single ascending dose, or SAD, and multiple ascending dose, or MAD, clinical trial of VK2735, a novel dual agonist of the glucagon-like peptide 1, or GLP-1, and glucose-dependent insulinotropic polypeptide, or GIP, receptors. VK2735 is being developed in both oral and subcutaneous formulations for the potential treatment of various metabolic disorders such as obesity.

In March 2023, we announced the completion of the Phase 1 trial. The study was a randomized, double-blind, placebo-controlled, SAD and MAD study in healthy adults. The primary objectives of the study included evaluation of the safety and tolerability of single and multiple doses of VK2735 delivered subcutaneously and the identification of VK2735 doses suitable for further clinical development. Study investigators also evaluated the pharmacokinetics of single and multiple doses of VK2735. Based upon the results from this Phase 1 study, in September 2023, we initiated the VENTURE study, a Phase 2 clinical trial of VK2735 in patients with obesity.

The Phase 2 VENTURE study was a randomized, double-blind, placebo-controlled study to evaluate the safety, tolerability, pharmacokinetics and weight loss efficacy of VK2735, administered subcutaneously, once weekly. The 13-week study enrolled adults who were obese (BMI >= 30 kg/m2) or adults who were overweight (BMI >= 27 kg/m2) with at least one weight-related co-morbidity condition. The primary endpoint of the study was the percent change in body weight from baseline to week 13, with secondary and exploratory endpoints evaluating a range of additional safety and efficacy measures. In October 2023, we announced completion of patient enrollment in the Phase 2 VENTURE study and on February 27, 2024, we announced that patients receiving weekly doses of VK2735 demonstrated statistically significant reductions in mean body weight after 13 weeks, ranging up to 14.7% from baseline. Patients receiving VK2735 also demonstrated statistically significant reductions in mean body weight relative to placebo, ranging up to 13.1%. VK2735 demonstrated encouraging safety and tolerability following 13 weeks of once-weekly dosing.

In June 2025, we announced the initiation of two Phase 3 clinical studies to evaluate the subcutaneous formulation of VK2735, VANQUISH-1 and VANQUISH-2. In November 2025, we announced completion of patient enrollment in the VANQUISH-1 study. In March 2026, we announced the completion of patient enrollment in the VANQUISH-2 study.

In March 2023, we announced the initiation of a Phase 1 clinical study to evaluate a novel oral formulation of VK2735. The study, which was an extension of our completed Phase 1 evaluation of subcutaneously administered VK2735, evaluated daily oral doses for 28 days. In March 2024, we announced that the 28-day MAD study results highlighted positive signs of clinical activity following treatment with oral VK2735. Cohorts receiving VK2735 demonstrated dose-dependent reductions in mean body weight from baseline, ranging up to approximately 5.3%. Oral VK2735 demonstrated encouraging safety and tolerability following 28 days of once-daily dosing.

S-2

In January 2025, we announced the initiation of a Phase 2 clinical trial of the oral tablet formulation of VK2735, and in August 2025, we announced positive top-line results from the trial. The Phase 2 VENTURE-Oral Dosing trial successfully achieved its primary and secondary endpoints, with patients receiving oral VK2735 demonstrating statistically significant reductions in body weight compared with placebo, ranging up to 12.2% from baseline. Additionally, the trial showed oral VK2735 treatment to be safe and well-tolerated through 13 weeks of daily dosing with the majority of treatment emergent adverse events being categorized as mild or moderate. We expect to initiate Phase 3 oral dosing studies in the fourth quarter of 2026.

In October 2025, we announced the initiation of an exploratory maintenance dosing study of VK2735. This study is intended to explore the feasibility of various VK2735 maintenance dosing regimens utilizing either the oral tablet or the subcutaneous formulation to sustain the initial weight loss achieved following subcutaneous dosing. In January 2026, we announced completion of enrollment in this study. In September 2026, we announced topline results from this study, which are included in the section titled “—Recent Developments—Positive Topline Results from Maintenance Study of GLP-1/GIP Agonist VK2735” below.

In March 2025, we entered into broad, multi-year manufacturing agreements, or the Manufacturing Agreements, with Corden Pharma Colorado, Inc. and its affiliates, or CordenPharma, covering both the active pharmaceutical ingredient, or API, and final finished product supply for VK2735.

Under the terms of the Manufacturing Agreements, we have secured dedicated capacity for the annual manufacture and supply of multiple metric tons of VK2735 API. In addition, CordenPharma will provide fill/finish capacity for both the injectable and oral formulations of VK2735. This includes dedicated manufacturing lines and an annual commitment to supply 100 million autoinjectors and an additional 100 million vial and syringe products for the subcutaneous formulation, as well as an annual capacity of over one billion oral VK2735 tablets. These API and final finished product capacities are further expandable at our option. In exchange for dedicated API and fill/finish capacity, we will make prepayments to CordenPharma, to be paid over the period from 2026 to 2028. These prepayments will be fully credited against future orders.

In 2024, we announced a new, internally developed Dual Amylin and Calcitonin Receptor Agonist, or DACRA, program for the treatment of obesity and highlighted the effects of treatment on body weight, food intake and metabolic profile in both healthy rats and in diet-induced obese mice. The results demonstrated that our DACRAs reduced food intake in lean rats in the period from 0 – 72 hours following a single subcutaneous dose. In April 2026, we announced that we filed an IND application for our Novel Amylin Agonist VK3019. In June 2026, we announced the initiation of a Phase 1 SAD clinical trial evaluating VK3019.

We are also developing VK2809, which is an orally available, tissue and receptor-subtype selective agonist of the thyroid hormone receptor beta, or TRß. In November 2019, we initiated the VOYAGE study, a Phase 2b clinical trial of VK2809 in patients with biopsy-confirmed non-alcoholic steatohepatitis, or NASH/MASH.

The VOYAGE study was a randomized, double-blind, placebo-controlled, multicenter trial designed to assess the efficacy, safety and tolerability of VK2809 in patients with biopsy-confirmed NASH/MASH and fibrosis ranging from stages F1 to F3. The primary endpoint of the study evaluated the relative change in liver fat content, as assessed by magnetic resonance imaging, proton density fat fraction from baseline to week 12 in subjects treated with VK2809 as compared to placebo. Secondary objectives included evaluation of histologic changes assessed by hepatic biopsy after 52 weeks of dosing.

In January 2023, we announced completion of patient enrollment in the VOYAGE study and in May 2023 we reported that the VOYAGE study successfully achieved its primary endpoint, with patients receiving VK2809 experiencing statistically significant reductions in liver fat content from baseline to Week 12 as compared to placebo.

In June 2024, we announced positive 52-week histologic data from the VOYAGE study with up to 75% of patients treated with VK2809 achieving NASH/MASH resolution with no worsening of fibrosis as compared to 29% for placebo (p=0.0001), up to 57% of VK2809-treated patients achieving &#x2265;1-stage improvement in fibrosis with no worsening of NASH/MASH as compared to 34% for placebo (p<0.05) and up to 48% of VK2809-treated patients achieving both resolution of NASH/MASH and a &#x2265;1-stage improvement in fibrosis as compared to 20% for placebo (p=0.01). Adverse events, including gastrointestinal-related adverse events, were similar among VK2809-treated

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patients vs. placebo at week 52 and consistent with prior data reported at week 12. VK2809 has been evaluated in eight completed clinical studies, which enrolled more than 400 subjects.

We are also developing VK0214, which is also an orally available, tissue and receptor-subtype selective agonist of TR&szlig; for X-linked adrenoleukodystrophy, or X-ALD, a rare X-linked, inherited neurological disorder characterized by a breakdown in the protective barriers surrounding brain and nerve cells. The disease, for which there is no approved treatment, is caused by mutations in a peroxisomal transporter of very long chain fatty acids, or VLCFA, known as ABCD1. As a result, transporter function is impaired and patients are unable to efficiently metabolize VLCFA. The TR&szlig; receptor is known to regulate expression of an alternative VLCFA transporter, known as ABCD2. Various preclinical models have demonstrated that increased expression of ABCD2 can lead to normalization of VLCFA metabolism. Preliminary data suggest that VK0214 stimulates ABCD2 expression in an in vitro model and reduces VLCFA levels in an in vivo model of X-ALD.

In June 2021, we initiated a Phase 1b clinical trial of VK0214 in patients with X-ALD. This trial was a multi-center, randomized, double-blind, placebo-controlled study in adult male patients with the adrenomyeloneuropathy, or AMN, form of X-ALD. The study enrolled patients across three cohorts: placebo, VK0214 20 mg daily, and VK0214 40 mg daily.

The primary objectives of the study were to evaluate the safety and tolerability of VK0214 administered once-daily over a 28-day dosing period. Secondary objectives included an evaluation of the pharmacokinetics of VK0214 following 28 days of dosing in this population. An exploratory objective was to evaluate the effects of VK0214 on plasma levels of VLCFAs in subjects with AMN. In October 2024, we announced results from the Phase 1b clinical trial, which showed VK0214 to be safe and well-tolerated following once-daily dosing over the 28-day study period. In addition, significant reductions were observed in plasma levels of VLCFAs and other lipids, as compared to placebo. Our intent is to pursue partnering or licensing opportunities for VK0214 prior to conducting additional clinical studies.

Other programs include VK5211, an orally available, non-steroidal selective androgen receptor modulator. In November 2017, we announced positive top-line results from a Phase 2 proof-of-concept clinical trial in 108 patients recovering from non-elective hip fracture surgery. Top-line data showed that the trial achieved its primary endpoint, demonstrating statistically significant, dose-dependent increases in total lean body mass, less head, following treatment with VK5211 as compared to placebo. The study also achieved certain secondary endpoints, demonstrating statistically significant increases in appendicular lean body mass and total lean body mass for all doses of VK5211, compared to placebo. VK5211 demonstrated encouraging safety and tolerability in this study, with no drug-related serious adverse events reported. Our intent is to continue to pursue partnering or licensing opportunities for VK5211 prior to conducting additional clinical studies.

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Our Development Pipeline

The following table highlights our current development pipeline:

Key: TR&szlig;, thyroid receptor beta; MASH, metabolic dysfunction-associated steatohepatitis; GLP-1, glucagon-like peptide 1; GIP, glucose-dependent insulinotropic polypeptide; X-ALD, X-linked adrenoleukodystrophy.

For a complete description of our business, financial condition, results of operations and other important information, we refer you to our filings with the SEC that are incorporated by reference in this prospectus supplement, including our Annual Report on Form 10-K for the year ended December 31, 2025, our Quarterly Report on Form 10-Q for the quarter ended March 31, 2026 and our Quarterly Report on Form 10-Q for the quarter ended June 30, 2026. For instructions on how to find copies of these documents, see the sections of this prospectus supplement titled &#x201c;Incorporation by Reference&#x201d; and &#x201c;Where You Can Find Additional Information&#x201d;.

Recent Developments

Concurrent Common Stock Offering

Concurrently with this offering, we are offering, pursuant to a separate prospectus supplement, shares of our common stock, plus up to an additional shares of our common stock that the underwriters of the concurrent common stock offering have the option to purchase from us. The completion of this offering is not contingent on the completion of the concurrent common stock offering, and the completion of the concurrent common stock offering is not contingent on the completion of this offering. Accordingly, you should not assume that the concurrent common stock offering will be consummated on the terms described in this prospectus supplement, if at all, or that we will receive any additional proceeds from the concurrent common stock offering. This prospectus supplement does not constitute an offer to sell, or the solicitation of an offer to buy, any securities being offered in the concurrent common stock offering. The prospectus supplement for the concurrent common stock offering does not constitute an offer to sell, or the solicitation of an offer to buy, any of the notes, or the shares of common stock, if any, issuable upon conversion of the notes, that we are offering pursuant to this prospectus supplement. See &#x201c;The Concurrent Common Stock Offering.&#x201d;

Positive Topline Results from Maintenance Study of GLP-1/GIP Agonist VK2735

On September 22, 2026, we announced positive top-line results from our maintenance study of VK2735, our dual agonist of the GLP-1 and GIP receptors. In this study, subjects receiving subcutaneous VK2735 demonstrated superior weight maintenance following the transition to less frequent dosing regimens compared with subjects transitioned to placebo. In addition, VK2735 demonstrated an encouraging safety and tolerability profile during the 12-week maintenance dosing period, with observed rates of GI-related adverse events comparable to placebo. We

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believe these results further differentiate VK2735 by demonstrating compelling weight loss maintenance via new long-term dosing regimens, including monthly and every-other-week administration. VK2735 is being developed in both subcutaneous and oral formulations for the potential treatment of various metabolic disorders such as obesity. We plan to explore oral maintenance dosing regimens in an upcoming part 2 to the current study.

Top-line study results include:

Body Weight Reductions &#x2013; Induction Phase

Participants in this study were randomized to receive weekly doses of VK2735 or placebo for 21 weeks. Starting in Week 3, VK2735 doses were escalated every two weeks until final doses of 15.0 mg, 17.5 mg, 20.0 mg, or 22.5 mg were achieved. Weight loss after 21 weeks of dosing ranged from approximately 16% to 19% compared with approximately 0% for placebo (p<0.0001 vs. baseline and placebo, all cohorts). Weight loss during the induction period was progressive in each cohort, with no evidence of plateau through 21 weeks of weekly dosing.

At 21 weeks in the combined VK2735 treatment groups, the proportion of participants demonstrating 5%, 10%, 15%, and 20% weight loss were 98%, 90%, 65%, and 32% as compared with 13%, 0%, 0%, and 0% for placebo (p<0.01 vs. placebo for each). Due to the progressive nature of observed weight loss, we believe that continued weight loss is likely to be observed with longer-term once-weekly dosing, as suggested by results from the exploratory control cohort in the maintenance phase, which demonstrated approximately 22% weight loss from baseline after 33 weeks.

Body Weight Maintenance &#x2013; Maintenance Phase

Following completion of the 21-week induction phase of the study, participants receiving weekly VK2735 treatment were transitioned to maintenance dosing regimens for an additional 12 weeks. During the maintenance dosing period, participants were randomized to a range of monthly (every four weeks) and every-other-week dosing regimens to evaluate the effect of less frequent dosing on weight maintenance.

Subjects randomized to every-other-week dosing regimens maintained up to 97% of mean weight loss achieved in the weekly induction period. This compares with 61% mean weight loss maintenance among subjects randomized to placebo (p<0.0001 vs. placebo). Separation from placebo was noted as early as four weeks following transition from weekly dosing.

Participants randomized to monthly dosing regimens successfully maintained up to 90% of mean weight loss achieved during the induction period, compared with 61% mean weight loss maintenance among subjects randomized to placebo (p=0.0002 vs. placebo). As with the transition to every-other-week dosing, separation from placebo was noted as early as four weeks following transition from weekly dosing.

An exploratory control arm in the study evaluated weight change in a cohort of participants who continued receiving weekly VK2735 doses of 17.5 mg (n=13). This cohort demonstrated mean weight loss of 21.7% from baseline (Week 0) (p<0.0001 vs. baseline), compared with 0.3% weight gain for placebo (p<0.0001 vs. placebo). Weight loss in this cohort was progressive through 33 weeks of treatment with no plateau observed.

Safety and Tolerability

VK2735 demonstrated highly encouraging tolerability during the maintenance phase of the trial following the transition from weekly dosing to every-other-week or monthly dosing regimens. Rates of gastrointestinal-related adverse events such as vomiting, nausea, diarrhea, and constipation were not meaningfully different from placebo over the 12-week maintenance window. Discontinuation rates, including discontinuations due to adverse events, were low during both the maintenance and induction portions of the trial.

Consistent with prior clinical studies, VK2735 also demonstrated an encouraging safety and tolerability profile during the 21-week induction phase of the trial. One subject (1%) in the induction period discontinued VK2735 treatment due to an adverse event. The most common adverse events were gastrointestinal, or GI, in nature, characterized as mild, and in-line with those expected from activation of the GLP-1 receptor. Despite the accelerated

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2-week titration schedule utilized in this study, rates of common GI adverse events such as nausea, vomiting, constipation, and diarrhea were similar to those reported in the prior Phase 2 study, which utilized 3-week titration steps. Among the combined VK2735 treatment groups, the incidence of GI-related adverse events was low and declined over time.

About the VK2735-102 Maintenance Study

The maintenance dosing study was a randomized, double-blind, placebo-controlled trial in approximately 180 adults with obesity (BMI &#x2265;30 kg/m2) and otherwise healthy. All participants received initial weekly subcutaneous doses of VK2735 or placebo for 21 weeks. Following Week 21, participants were transitioned to a range of VK2735 maintenance dosing options including monthly, every other week, or weekly subcutaneous injections, or placebo. The objectives of the study were to evaluate the safety, tolerability, and pharmacokinetic profile of VK2735 under these various dosing regimens. Exploratory endpoints assessed change in body weight from baseline, as well as change in body weight from Week 21 to the end of the study at Week 33.

Corporate and Other Information

We were incorporated under the laws of the State of Delaware on September 24, 2012. Our principal executive offices are located at 9920 Pacific Heights Blvd, Suite 500, San Diego, CA 92121, and our telephone number is (858) 704-4660. Our website address is www.vikingtherapeutics.com. We do not incorporate the information on, or accessible through, our website into this prospectus supplement, and you should not consider any information on, or accessible through, our website as part of this prospectus supplement. We have included our website address in this prospectus supplement solely as an inactive textual reference.

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The Offering

The summary below describes the principal terms of the notes. Certain of the terms of the notes described below are subject to important limitations and exceptions that are described in more detail under the caption &#x201c;Description of Notes.&#x201d; As used in this section, &#x201c;we,&#x201d; &#x201c;our&#x201d; and &#x201c;us&#x201d; refer to Viking Therapeutics, Inc. and not to its subsidiaries.

Issuer Viking Therapeutics, Inc.

Notes $ aggregate principal amount of % convertible senior notes due 2032. We have granted the underwriters an option, which is exercisable within 30 days after the date of this prospectus supplement, to purchase up to an additional $ aggregate principal amount of notes solely to cover over-allotments.

Settlement , 2026.

Ranking The notes will be our senior, unsecured obligations and will be:

&#x2022;
equal in right of payment with our existing and future senior, unsecured indebtedness;
&#x2022;
senior in right of payment to our existing and future indebtedness that is expressly subordinated to the notes;
&#x2022;
effectively subordinated to our existing and future secured indebtedness, to the extent of the value of the collateral securing that indebtedness; and
&#x2022;
structurally subordinated to all existing and future indebtedness and other liabilities, including trade payables, and (to the extent we are not a holder thereof) preferred equity, if any, of our subsidiaries.

As of June 30, 2026, excluding our subsidiaries, we had no indebtedness for borrowed money, and our subsidiaries had approximately $79.8 million of indebtedness and other liabilities.

Maturity October 15, 2032, unless earlier repurchased, redeemed or converted.

Interest % per annum, payable semi-annually in arrears on April 15 and October 15 of each year, beginning on April 15, 2027. In addition, special interest will accrue on the notes in the circumstances described under the caption &#x201c;Description of Notes&#x2014;Events of Default&#x2014;Special Interest as Sole Remedy for Certain Reporting Defaults&#x201d;.

Conversion Rights Noteholders may convert their notes at their option only in the following circumstances:

&#x2022;
during any calendar quarter commencing after the calendar quarter ending on December 31, 2026, if the last reported sale price per share of our common stock exceeds 130% of the conversion price for each of at least 20 trading days during the 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter;

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during the five consecutive business days immediately after any 10 consecutive trading day period (such 10 consecutive trading day period, the &#x201c;measurement period&#x201d;) in which the trading price per $1,000 principal amount of notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day;
&#x2022;
upon the occurrence of certain corporate events or distributions on our common stock, as described in this prospectus supplement;
&#x2022;
if we call such notes for redemption; and
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at any time from, and including, July 15, 2032 until the close of business on the second scheduled trading day immediately before the maturity date.

We will settle conversions by paying or delivering, as applicable, cash, shares of our common stock or a combination of cash and shares of our common stock, at our election, based on the applicable conversion rate(s). If we elect to deliver cash or a combination of cash and shares of our common stock, then the consideration due upon conversion will be determined over an observation period consisting of 25 &#x201c;VWAP trading days&#x201d; (as defined in this prospectus supplement). The initial conversion rate is shares per $1,000 principal amount of notes, which represents an initial conversion price of approximately $ per share, and is subject to adjustment as described in this prospectus supplement.

If a &#x201c;make-whole fundamental change&#x201d; (as defined in this prospectus supplement) occurs, then we will in certain circumstances increase the conversion rate for a specified period of time.

See &#x201c;Description of Notes&#x2014;Conversion Rights.&#x201d;

Provisional Redemption We will have the right, at our election, to redeem (a &#x201c;provisional redemption&#x201d;) all, or any portion (subject to certain limitations described below), of the notes, at any time, and from time to time, on or after October 22, 2029 and on or before the 25th scheduled trading day immediately before the maturity date, at a cash redemption price equal to the principal amount of the notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date, but only if the last reported sale price per share of our common stock exceeds 130% of the conversion price on (x) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we send the related redemption notice; and (y) the trading day immediately before the date we send such notice. However, we may not redeem less than all of the outstanding notes pursuant to a provisional redemption unless at least $100.0 million aggregate principal amount of notes are outstanding and not called for redemption as of the time we send the related redemption notice. In addition, calling any note for provisional redemption will constitute a make-whole fundamental change with respect to that note, in which case the conversion rate applicable to the conversion of that note will be increased in certain circumstances if it is converted after it is called for provisional redemption. See &#x201c;Description of Notes&#x2014;Optional Redemption&#x2014;Provisional Redemption.&#x201d;

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Optional Cleanup

Redemption We will have the right, at our election, to redeem (a &#x201c;cleanup redemption&#x201d;) all, but not less than all, of the notes, at any time, at a cash redemption price equal to the principal amount of the notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date, but only if the principal amount of the notes outstanding at the time we send the related redemption notice is less than 15% of the aggregate principal amount of the notes issued in this offering (including any additional notes issued pursuant to any exercise of the underwriters&#x2019; option to purchase additional notes). In addition, calling the notes for cleanup redemption will constitute a make-whole fundamental change, which will require us to increase the conversion rate in certain circumstances for a specified period of time. See &#x201c;Description of Notes&#x2014;Optional Redemption&#x2014;Cleanup Redemption.&#x201d;

Repurchase at the Option of

the Noteholders After a

Fundamental Change If a &#x201c;fundamental change&#x201d; (as defined in this prospectus supplement) occurs, then, except as described in this prospectus supplement, noteholders may require us to repurchase their notes at a cash repurchase price equal to the principal amount of the notes to be repurchased, plus accrued and unpaid interest, if any, to, but excluding, the fundamental change repurchase date. See &#x201c;Description of Notes&#x2014;Fundamental Change Permits Noteholders to Require Us to Repurchase Notes.&#x201d;

Trustee, Paying Agent and

Conversion Agent U.S. Bank Trust Company, National Association.

No Public Market The notes are a new class of securities for which no public market currently exists. We do not intend to apply to list the notes on any securities exchange or for quotation on any inter-dealer quotation system. Accordingly, a liquid market for the notes may never develop. Certain of the underwriters have advised us that they intend to make a market in the notes. However, they are not obligated to do so and may discontinue any market-making activity at any time and without notice.

The Nasdaq Capital Market

Symbol Our common stock is listed on the Nasdaq Capital Market under the symbol &#x201c;VKTX.&#x201d; On September 22, 2026, the last reported sale price of our common stock was $40.85 per share.

Use of Proceeds We estimate that the net proceeds to us from this offering will be approximately $ million (or approximately $ million if the underwriters exercise in full their option to purchase additional notes), after deducting the underwriting discounts and commissions and our estimated offering expenses. We intend to use the net proceeds from this offering, together with the net proceeds from the concurrent common stock offering described below, if it is consummated, for the continued clinical development, advancement and commercialization of our VK2735 and VK3019 programs and for other general research and development, working capital and general corporate purposes. We may also use a portion of the net proceeds to acquire or invest in other businesses, products and technologies that are complementary to our own, although we have no current plans, commitments or arrangements to do so. See &#x201c;Use of Proceeds.&#x201d;

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Concurrent Common Stock

Offering Concurrently with this offering, we are offering, pursuant to a separate prospectus supplement, shares of our common stock, plus up to an additional shares of our common stock that the underwriters of the concurrent common stock offering have the option to purchase from us. We estimate that the net proceeds to us from the concurrent common stock offering, if it is consummated, will be approximately $ million (or approximately $ million if the underwriters of the concurrent common stock offering exercise in full their option to purchase additional shares of common stock), after deducting the underwriting discounts and commissions and our estimated offering expenses.

The completion of this offering is not contingent on the completion of the concurrent common stock offering, and the completion of the concurrent common stock offering is not contingent on the completion of this offering. Accordingly, you should not assume that the concurrent common stock offering will be consummated on the terms described in this prospectus supplement, if at all, or that we will receive any additional proceeds from the concurrent common stock offering. This prospectus supplement does not constitute an offer to sell, or the solicitation of an offer to buy, any securities being offered in the concurrent common stock offering. The prospectus supplement for the concurrent common stock offering does not constitute an offer to sell, or the solicitation of an offer to buy, any of the notes, or the shares of common stock, if any, issuable upon conversion of the notes, we are offering pursuant to this prospectus supplement. See &#x201c;The Concurrent Common Stock Offering.&#x201d;

Risk Factors Investing in the notes involves risks. See &#x201c;Risk Factors.&#x201d;

Material U.S. Federal Income

Tax Considerations For a description of material U.S. federal income tax considerations of purchasing, owning, converting and disposing of the notes and owning and disposing of shares of our common stock, if any, issuable upon conversion of the notes, see &#x201c;Material U.S. Federal Income Tax Considerations.&#x201d;

Book-Entry Form We will initially issue the notes in the form of one or more global notes registered in the name of Cede & Co., as nominee of The Depository Trust Company (&#x201c;DTC&#x201d;), without interest coupons, which we will deposit with the trustee as custodian for DTC. Beneficial interests in global notes will be shown on, and transfers of global notes will be effected only through, the records maintained by DTC. Except in limited circumstances, we will not issue certificated notes. See &#x201c;Description of Notes&#x2014;Book Entry, Settlement and Clearance.&#x201d;

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Risk Factors

Investing in the notes involves a high degree of risk. In addition to the other information included and incorporated by reference in this prospectus supplement or the accompanying prospectus, you should carefully consider the risks described or referred to below before deciding to purchase the notes. The occurrence of any of these risks may materially harm our business, results of operations and financial condition. As a result, the trading price of the notes and our common stock may decline, and you might lose part or all of your investment. As used in this section, &#x201c;we,&#x201d; &#x201c;our&#x201d; and &#x201c;us&#x201d; refer to Viking Therapeutics, Inc. and not to its subsidiaries.

The notes will be effectively subordinated to our existing and future secured indebtedness and structurally subordinated to the liabilities of our subsidiaries.

The notes will be our senior, unsecured obligations and will rank equal in right of payment with our existing and future senior, unsecured indebtedness, senior in right of payment to our existing and future indebtedness that is expressly subordinated to the notes and effectively subordinated to our existing and future secured indebtedness, to the extent of the value of the collateral securing that indebtedness. In addition, because none of our subsidiaries will guarantee the notes, the notes will be structurally subordinated to all existing and future indebtedness and other liabilities, including trade payables, and (to the extent we are not a holder thereof) preferred equity, if any, of our subsidiaries. As of June 30, 2026, excluding our subsidiaries, we had no indebtedness for borrowed money, and our subsidiaries had approximately $79.8 million of indebtedness and other liabilities. The indenture governing the notes will not prohibit us or our subsidiaries from incurring additional indebtedness, including senior or secured indebtedness, in the future.

If a bankruptcy, liquidation, dissolution, reorganization or similar proceeding occurs with respect to us, then the holders of any secured indebtedness that we may have in the future may proceed directly against the assets securing that indebtedness. Accordingly, those assets would not be available to satisfy any outstanding amounts under our unsecured indebtedness, including the notes, unless the secured indebtedness is first paid in full. The remaining assets, if any, would then be allocated pro rata among the holders of our senior indebtedness, including the notes. There may be insufficient assets to pay all amounts then due.

If a bankruptcy, liquidation, dissolution, reorganization or similar proceeding occurs with respect to any of our subsidiaries, then we, as a direct or indirect common equity owner of that subsidiary (and, accordingly, holders of our unsecured and unguaranteed indebtedness, including the notes), will be subject to the prior claims of that subsidiary&#x2019;s creditors, including trade creditors and preferred equity holders. We may never receive any amounts from that subsidiary to satisfy amounts due under the notes.

We conduct a significant amount of our operations through our subsidiaries and will rely on our subsidiaries to make payments under the notes.

We conduct a significant amount of our operations through our subsidiaries. Accordingly, our ability to pay amounts due on the notes will depend on the cash flows of our subsidiaries and their ability to make distributions to us. None of our subsidiaries has guaranteed or otherwise become obligated with respect to the notes. Furthermore, none of our subsidiaries is under any obligation to make payments to us, and any payments to us would depend on the earnings or financial condition of our subsidiaries and various business considerations. Statutory, contractual or other restrictions may also limit our subsidiaries&#x2019; ability to pay dividends or make distributions, loans or advances to us. For these reasons, we may not have access to any assets or cash flows of our subsidiaries to make payments on the notes.

Our indebtedness and liabilities could limit the cash flow available for our operations, expose us to risks that could adversely affect our business, financial condition and results of operations and impair our ability to satisfy our obligations under the notes.

As of June 30, 2026, we had no consolidated indebtedness for borrowed money. We will incur $ million (or, if the underwriters exercise in full their option to purchase additional notes, $ million) principal amount of additional indebtedness as a result of this offering. We may also incur additional indebtedness to meet future financing needs. Our indebtedness could have significant negative consequences for our security holders and our business, results of operations and financial condition by, among other things:

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increasing our vulnerability to adverse economic and industry conditions;
&#x2022;
limiting our ability to obtain additional financing;
&#x2022;
requiring the dedication of a substantial portion of our cash flow from operations to service our indebtedness, which will reduce the amount of cash available for other purposes;
&#x2022;
limiting our flexibility to plan for, or react to, changes in our business;
&#x2022;
diluting the interests of our existing stockholders as a result of issuing shares of our common stock upon conversion of the notes; and
&#x2022;
placing us at a possible competitive disadvantage with competitors that are less leveraged than us or have better access to capital.

Our business may not generate sufficient funds, and we may otherwise be unable to maintain sufficient cash reserves, to pay amounts due under our indebtedness, including the notes, and our cash needs may increase in the future. In addition, future indebtedness that we may incur may contain financial and other restrictive covenants that limit our ability to operate our business, raise capital or make payments under our other indebtedness. If we fail to comply with these covenants or to make payments under our indebtedness when due, then we would be in default under that indebtedness, which could, in turn, result in that and our other indebtedness becoming immediately payable in full.

We may be unable to raise the funds necessary to repurchase the notes for cash following a fundamental change or to pay any cash amounts due upon maturity or conversion of the notes, and our other indebtedness may limit our ability to repurchase the notes or to pay any cash amounts due upon their maturity or conversion.

Noteholders may, subject to limited exceptions described in this prospectus supplement, require us to repurchase their notes following a fundamental change at a cash repurchase price generally equal to the principal amount of the notes to be repurchased, plus accrued and unpaid interest, if any. See &#x201c;Description of Notes&#x2014;Fundamental Change Permits Noteholders to Require Us to Repurchase Notes.&#x201d; Upon maturity of the notes, we must pay their principal amount and accrued and unpaid interest in cash, unless they have been previously repurchased, redeemed or converted. In addition, upon conversion, we will satisfy part or all of our conversion obligation in cash unless we elect to settle conversions solely in shares of our common stock. We may not have enough available cash or be able to obtain financing at the time we are required to repurchase the notes or pay any cash amounts due upon their maturity or conversion. In addition, applicable law, regulatory authorities and the agreements governing our other indebtedness may restrict our ability to repurchase the notes or to pay any cash amounts due upon their maturity or conversion. Our failure to repurchase notes or to pay any cash amounts due upon their maturity or conversion when required will constitute a default under the indenture. A default under the indenture or the fundamental change itself could also lead to a default under agreements governing our other indebtedness, which may result in that other indebtedness becoming immediately payable in full. We may not have sufficient funds to satisfy all amounts due under the other indebtedness and the notes.

Not all events that may adversely affect the trading price of the notes and our common stock will result in an adjustment to the conversion rate.

We will adjust the conversion rate of the notes for certain events, including:

&#x2022;
certain stock dividends, splits and combinations;
&#x2022;
the issuance of certain rights, options or warrants to holders of our common stock;
&#x2022;
certain distributions of assets, debt securities, capital stock or other property to holders of our common stock;
&#x2022;
cash dividends on our common stock; and

S-13

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certain tender or exchange offers.

See &#x201c;Description of Notes&#x2014;Conversion Rights&#x2014;Conversion Rate Adjustments.&#x201d; We are not required to adjust the conversion rate for other events, such as third-party tender offers or an issuance of our common stock (or securities convertible into, or exercisable or exchangeable for, our common stock) for cash, that may adversely affect the trading price of the notes and our common stock. An event may occur that adversely affects the noteholders and the trading price of the notes and the underlying shares of our common stock but that does not result in an adjustment to the conversion rate.

Not all significant restructuring transactions will constitute a fundamental change, in which case you will not have the right to require us to repurchase your notes for cash.

If certain corporate events called &#x201c;fundamental changes&#x201d; occur, then, subject to limited exceptions described in this prospectus supplement, you will have the right to require us to repurchase your notes for cash. See &#x201c;Description of Notes&#x2014;Fundamental Change Permits Noteholders to Require Us to Repurchase Notes.&#x201d; However, the definition of &#x201c;fundamental change&#x201d; is limited to specific corporate events and does not include all events that may adversely affect our financial condition or the trading price of the notes. For example, a leveraged recapitalization, refinancing, restructuring or acquisition by us may not constitute a fundamental change that would require us to repurchase the notes. Nonetheless, these events could significantly increase the amount of our indebtedness, harm our credit rating or adversely affect our capital structure and the trading price of the notes.

The increase to the conversion rate resulting from a make-whole fundamental change may not adequately compensate noteholders for the lost option value of their notes. In addition, a variety of transactions that do not constitute a make-whole fundamental change may significantly reduce the option value of the notes without a corresponding increase to the conversion rate.

If certain corporate events that constitute a &#x201c;make-whole fundamental change&#x201d; occur, then we will, in certain circumstances, temporarily increase the conversion rate. See &#x201c;Description of Notes&#x2014;Conversion Rights&#x2014;Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change.&#x201d; The amount of the increase to the conversion rate will depend on the date on which the make-whole fundamental change becomes effective and the applicable &#x201c;stock price.&#x201d; While the increase to the conversion rate is designed to compensate noteholders for the lost option value of their notes resulting from a make-whole fundamental change, the increase is only an approximation and may not adequately compensate noteholders for the loss in option value. In addition, if the applicable &#x201c;stock price&#x201d; is greater than $ per share or less than $ per share (in each case, subject to adjustment), then we will not increase the conversion rate for the make-whole fundamental change. Moreover, we will not increase the conversion rate pursuant to these provisions to an amount that exceeds shares of our common stock per $1,000 principal amount of notes, subject to adjustment.

Furthermore, the definition of make-whole fundamental change is limited to certain specific transactions. Accordingly, the make-whole fundamental change provisions of the indenture will not protect noteholders from other transactions that could significantly reduce the option value of the notes. For example, a spin-off or sale of a subsidiary or business division with volatile earnings, or a change in our line of business, could significantly affect the trading characteristics of our common stock and reduce the option value of the notes without constituting a make-whole fundamental change that results in a temporary increase to the conversion rate.

In addition, our obligation to increase the conversion rate in connection with a make-whole fundamental change could be considered a penalty, in which case its enforceability would be subject to general principles of reasonableness and equitable remedies.

There is currently no trading market for the notes. If an active trading market for the notes does not develop, then noteholders may be unable to sell their notes at desired times or prices, or at all.

The notes are a new class of securities for which no market currently exists. We do not intend to apply to list the notes on any securities exchange or for quotation on any inter-dealer quotation system. Although certain of the underwriters have advised us that they intend to make a market in the notes, they are not obligated to do so and may discontinue any market-making activity at any time and without notice. Accordingly, an active market for the notes may never develop, and, even if one develops, it may not be maintained. If an active trading market for the notes does not develop or is not maintained, then

S-14

the market price and liquidity of the notes will be adversely affected and noteholders may not be able to sell their notes at desired times or prices, or at all.

The liquidity of the trading market, if any, and future trading prices of the notes will depend on many factors, including, among other things, the trading price and volatility of our common stock, prevailing interest rates, our dividend yield, financial condition, results of operations, business, prospects and credit quality relative to our competitors, the market for similar securities and the overall securities market. Many of these factors are beyond our control. Historically, the market for convertible debt has been volatile. Market volatility could significantly harm the market for the notes, regardless of our financial condition, results of operations, business, prospects or credit quality.

The trading price of our common stock, the condition of the financial markets, prevailing interest rates and other factors could significantly affect the trading price of the notes.

We expect that the trading price of our common stock will significantly affect the trading price of the notes, which could result in greater volatility in the trading price of the notes than would be expected for non-convertible securities. The trading price of our common stock will likely continue to fluctuate in response to the factors described or referred to elsewhere in this section and under the caption &#x201c;Disclosure Regarding Forward-Looking Statements,&#x201d; among others, many of which are beyond our control.

In addition, the condition of the financial markets and changes in prevailing interest rates can have an adverse effect on the trading price of the notes. For example, prevailing interest rates have fluctuated in the past and are likely to fluctuate in the future, and we would expect an increase in prevailing interest rates to depress the trading price of the notes. An increase in short- or long-term interest rates, including as a result of a rise in actual or expected inflation, could cause the trading price of the notes to fall significantly.

The issuance or sale of shares of our common stock, including pursuant to the concurrent common stock offering, or rights to acquire shares of our common stock, could depress the trading price of our common stock and the notes.

Concurrently with this offering, we are offering $ of our common stock, plus up to an additional $ of our common stock that the underwriters of the concurrent common stock offering have the option to purchase from us. We may also conduct future offerings of common stock, preferred stock or other securities that are convertible into, or exercisable or exchangeable for, our common stock to finance our operations or fund acquisitions, or for other purposes. In addition, as of June 30, 2026, we have reserved 5,990,015 shares of our common stock issuable upon the exercise of outstanding options, 1,813,501 shares of our common stock for future issuance upon vesting of outstanding restricted stock units, 9,481,886 shares of our common stock for issuance under our 2024 Equity Incentive Plan and 5,462,753 shares of our common stock for issuance under our 2024 Employee Stock Purchase Plan. The indenture for the notes will not restrict our ability to issue additional equity securities in the future. If we issue additional shares of our common stock or rights to acquire shares of our common stock, if any of our existing stockholders sells a substantial amount of our common stock, or if the market perceives that such issuances or sales may occur, then the trading price of our common stock and, accordingly, the notes may significantly decline. In addition, our issuance of additional shares of common stock will dilute the ownership interests of our existing common stockholders, including noteholders who have received shares of our common stock upon conversion of their notes.

This offering is not contingent on the consummation of the concurrent common stock offering, and vice versa.

The completion of this offering is not contingent on the completion of the concurrent common stock offering, and the completion of the concurrent common stock offering is not contingent on the completion of this offering. Accordingly, you should not assume that the concurrent common stock offering will be consummated on the terms described in this prospectus supplement, if at all, or that we will receive any additional proceeds from the concurrent common stock offering. This prospectus supplement does not constitute an offer to sell, or the solicitation of an offer to buy, any securities being offered in the concurrent common stock offering. See &#x201c;The Concurrent Common Stock Offering.&#x201d;

We will make only very limited covenants in the indenture, and these limited covenants may not protect your investment.

Many debt instruments contain provisions that restrict the borrower&#x2019;s activities and operations in a manner that is designed to preserve the borrower&#x2019;s ability to make payments on the related indebtedness when due. These provisions include

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financial and operating covenants, and restrictions on the payments of dividends, the incurrence of indebtedness or the issuance or repurchase of securities by the borrower or any of its subsidiaries. The indenture for the notes will not contain any of these covenants or restrictions or otherwise place any meaningful restrictions on our ability to operate our business as management deems appropriate. As a result, your investment in the notes may not be as protected as an investment in an instrument that contains some or all of these types of covenants and restrictions.

Regulatory actions, changes in market conditions and other events may adversely affect the trading price and liquidity of the notes and the ability of investors to implement a convertible note arbitrage trading strategy.

We expect that many investors in the notes, including potential purchasers of the notes from investors in this offering, will seek to employ a convertible note arbitrage strategy. Under this strategy, investors typically short sell a certain number of shares of our common stock and adjust their short position over time while they continue to hold the notes. Investors may also implement this type of strategy by entering into swaps on our common stock in lieu of, or in addition to, short selling shares of our common stock.

The SEC and other regulatory authorities have implemented various rules and taken certain actions, and may in the future adopt additional rules and take other actions, that may impact those engaging in short selling activity involving equity securities (including our common stock). These rules and actions include Rule 201 of SEC Regulation SHO, the adoption by the Financial Industry Regulatory Authority, Inc., and the national securities exchanges of a &#x201c;limit up-limit down&#x201d; program, the imposition of market-wide circuit breakers that halt trading of securities for certain periods following specific market declines, and the implementation of certain regulatory reforms required by the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010. Any governmental or regulatory action that restricts investors&#x2019; ability to effect short sales of our common stock or enter into equity swaps on our common stock could depress the trading price of, and the liquidity of the market for, the notes.

In addition, the liquidity of the market for our common stock and other market conditions could deteriorate, which could reduce, or eliminate entirely, the number of shares available for lending in connection with short sale transactions and the number of counterparties willing to enter into an equity swap on our common stock with a note investor. These and other market events could make implementing a convertible note arbitrage strategy prohibitively expensive or infeasible. If investors in this offering or potential purchasers of the notes that seek to employ a convertible note arbitrage strategy are unable to do so on commercial terms, or at all, then the trading price of, and the liquidity of the market for, the notes may significantly decline.

You may be subject to tax if we adjust, or fail to adjust, the conversion rate of the notes, even though you will not receive a corresponding cash distribution.

We will adjust the conversion rate of the notes in certain circumstances, including the payment of cash dividends. Adjustments (or failures to make adjustments) that have the effect of increasing your proportionate interest in our assets or earnings and profits may in some circumstances result in a deemed distribution, for U.S. federal income tax purposes, to you even though no cash or property is received. Adjustments to the conversion rate made pursuant to a bona fide, reasonable adjustment formula that has the effect of preventing the dilution of the interest of the holders of the notes, however, will generally not be considered to result in a deemed distribution to you. In addition, if we do not adjust (or adjust adequately) the conversion rate after an event that increases your proportionate interest in us, then you could be treated as having received a deemed taxable dividend. For example, if we adjust the conversion rate as a result of a dividend that is taxable to holders of our common stock, such as a cash dividend, then you may be deemed, for U.S. federal income tax purposes, to have received a taxable dividend to the extent of our earnings and profits, without the receipt of any cash or property. If a make-whole fundamental change occurs prior to the maturity date, under some circumstances, we will increase the conversion rate for notes converted in connection with that make-whole fundamental change. Such increase may also be treated as a distribution subject to U.S. federal income tax as a dividend.

If you are subject to backup withholding, or if you are a non-U.S. holder (as defined in &#x201c;Material U.S. Federal Income Tax Considerations&#x201d;) subject to U.S. federal withholding tax, such withholding may be withheld from or set off against subsequent payments on the notes or our common stock owned by you or from any proceeds of any subsequent sale, exchange or other disposition of such notes (including the retirement of such notes) or such common stock or other funds or assets held by you. The Internal Revenue Service has issued proposed regulations addressing the amount and timing of deemed distributions, obligations of withholding agents and filing and notice obligations of issuers, which, if adopted, could affect the U.S. federal income tax treatment of a holder of notes deemed to receive such a distribution. See &#x201c;Description of

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Notes&#x2014;Conversion Rights&#x2014;Conversion Rate Adjustments,&#x201d; &#x201c;Description of Notes&#x2014;Conversion Rights&#x2014;Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change&#x201d; and &#x201c;Material U.S. Federal Income Tax Considerations.&#x201d;

A rating agency may not rate the notes or may assign a rating that is lower than expected.

We do not intend to seek to have the notes rated by any rating agency. However, if one or more rating agencies rate the notes and assign a rating that is lower than the rating that investors expect, or reduce their rating in the future, then the trading price of our common stock and the notes could significantly decline.

In addition, market perceptions of our creditworthiness will directly affect the trading price of the notes. Accordingly, if a ratings agency rates any of our indebtedness in the future, or puts us on credit watch, then the trading price of the notes will likely decline.

Provisions in the indenture could delay or prevent an otherwise beneficial takeover of us.

Certain provisions in the notes and the indenture could make a third-party attempt to acquire us more difficult or expensive. For example, if a takeover constitutes a fundamental change, then, except as described in this prospectus supplement, noteholders will have the right to require us to repurchase their notes for cash. In addition, if a takeover constitutes a make-whole fundamental change, then we may be required to temporarily increase the conversion rate. In either case, and in other cases, our obligations under the notes and the indenture could increase the cost of acquiring us or otherwise discourage a third party from acquiring us, including in a transaction that noteholders or holders of our common stock may view as favorable.

You may be unable to convert your notes before July 15, 2032, and the trading price of the notes could be less than the value of the consideration into which they could otherwise be converted.

Before July 15, 2032, you may convert your notes only if specific conditions are met. If these conditions are not met, then you will not be able to convert your notes and receive the cash, shares of our common stock or combination of cash and shares, as applicable, into which the notes would otherwise be convertible. As a result, the notes may trade at prices that are less than the value of the consideration into which they would otherwise be convertible.

Fluctuations in the trading price of our common stock after you elect to convert your notes may cause you to receive less valuable consideration than expected.

We will generally have the right to settle conversions in cash, shares of our common stock or a combination of cash and shares. If we elect to settle conversions solely in cash or in a combination of cash and shares, then the consideration due upon conversion will be determined based on the volume-weighted average price of our common stock during the related &#x201c;observation period,&#x201d; which is defined under the caption &#x201c;Description of Notes&#x2014;Definitions&#x201d; and will consist of 25 &#x201c;VWAP trading days.&#x201d; Except in certain circumstances, the observation period will begin after the related conversion date. Accordingly, a considerable amount of time may lapse between the time you elect to convert your notes and the time you receive the consideration due upon conversion, and if the trading price of our common stock declines during this time, then you may receive less consideration, or consideration that is less valuable, than expected.

Your investment in the notes may be harmed if we redeem the notes.

We will have the right to redeem the notes in certain circumstances before the maturity date. See &#x201c;Description of Notes&#x2014;Optional Redemption.&#x201d; If we redeem your notes, then you may not be entitled to benefit from potential future appreciation in the trading price of our common stock, and you may be unable to reinvest any proceeds from the redemption in comparable investments at favorable interest rates. In addition, we will be permitted, in certain circumstances, to redeem less than all of the outstanding notes in connection with a provisional redemption. A redemption of less than all of the outstanding notes will likely harm the liquidity of the market for the unredeemed notes following the redemption. Accordingly, if your notes are not redeemed in a partial redemption, then you may be unable to sell your notes at the times you desire or at favorable prices, if at all, and the trading price of your notes may decline.

S-17

We have broad discretion in how we use the proceeds of this offering and, if it is consummated, the concurrent common stock offering, and may not use these proceeds effectively, which could affect our results of operations and cause our stock price to decline.

Although we have described in this prospectus supplement, under the caption &#x201c;Use of Proceeds,&#x201d; how we currently intend to use the proceeds to us from this offering and, if it is consummated, the concurrent common stock offering, our management will have broad discretion to apply the net proceeds, and investors will rely on our judgment in spending the net proceeds with only limited information about our specific intentions for the use of the net proceeds. Our management may use the proceeds in ways that do not earn a profit or otherwise result in the creation of stockholder value. In addition, pending our use of the proceeds, we may invest the proceeds from this offering in a manner that does not produce income or that may lose value.

The accounting method for the notes could adversely affect our reported financial condition and results.

The accounting method for reflecting the notes on our balance sheet, accruing interest expense for the notes and reflecting the underlying shares of our common stock in our reported diluted earnings per share may adversely affect our reported earnings and financial condition.

In accordance with applicable accounting standards, we expect that the notes we are offering will be reflected as a liability on our balance sheets, with the initial carrying amount equal to the principal amount of the notes, net of issuance costs. The issuance costs will be treated as a debt discount for accounting purposes, which will be amortized into interest expense over the term of the notes. As a result of this amortization, the interest expense that we expect to recognize for the notes for accounting purposes will be greater than the cash interest payments we will pay on the notes, which will result in lower reported income.

In addition, we expect that the shares underlying the notes will be reflected in our diluted earnings per share using the &#x201c;if converted&#x201d; method. Under that method, diluted earnings per share would generally be calculated assuming that all the notes were converted solely into shares of our common stock at the beginning of the reporting period, unless the result would be anti-dilutive. The application of the if-converted method may reduce our reported diluted earnings per share, and accounting standards may change in the future in a manner that may adversely affect our diluted earnings per share.

Furthermore, if any of the conditions to the convertibility of the notes is satisfied, then we may be required under applicable accounting standards to reclassify the liability carrying value of the notes as a current, rather than a long-term, liability. This reclassification could be required even if no noteholders convert their notes and could materially reduce our reported working capital.

We have not reached a final determination regarding the accounting treatment for the notes, and the description above is preliminary. Accordingly, we may account for the notes in a manner that is significantly different than described above.

Because the notes will initially be held in book-entry form, noteholders must rely on DTC&#x2019;s procedures to exercise their rights and remedies.

We will initially issue the notes in the form of one or more &#x201c;global notes&#x201d; registered in the name of Cede & Co., as nominee of DTC. Beneficial interests in global notes will be shown on, and transfers of global notes will be effected only through, the records maintained by DTC. Except in limited circumstances, we will not issue certificated notes. See &#x201c;Description of Notes&#x2014;Book Entry, Settlement and Clearance.&#x201d; Accordingly, if you own a beneficial interest in a global note, then you will not be considered an owner or holder of the notes. Instead, DTC or its nominee will be the sole holder of the notes. Payments of principal, interest and other amounts on global notes will be made to the paying agent, who will remit the payments to DTC. We expect that DTC will then credit those payments to the DTC participant accounts that hold book-entry interests in the global notes and that those participants will credit the payments to indirect DTC participants. Unlike persons who have certificated notes registered in their names, owners of beneficial interests in global notes will not have the direct right to act on our solicitations for consents or requests for waivers or other actions from noteholders. Instead, those beneficial owners will be permitted to act only to the extent that they have received appropriate proxies to do so from DTC or, if applicable, a DTC participant. The applicable procedures for the granting of these proxies may not be sufficient to enable owners of beneficial interests in global notes to vote on any requested actions on a timely basis.

S-18

Holding notes will not, in itself, confer any rights with respect to our common stock.

Noteholders will generally not be entitled to any rights with respect to our common stock (including voting rights and rights to receive any dividends or other distributions on our common stock). However, noteholders will be subject to all changes affecting our common stock to the extent the trading price of the notes depends on the market price of our common stock and to the extent they receive shares of our common stock upon conversion of their notes. For example, if we propose an amendment to our charter documents that requires stockholder approval, then a noteholder will not, as such, be entitled to vote on the amendment, although the noteholder will be subject to any changes implemented by that amendment in the powers, preferences or special rights of our common stock.

S-19

Disclosure Regarding Forward-Looking Statements

This prospectus supplement and the accompanying base prospectus, including the documents incorporated by reference herein and therein, contain forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act, which statements involve substantial risks and uncertainties. Forward-looking statements generally relate to future events or our future financial or operating performance. In some cases, you can identify forward-looking statements because they contain words such as &#x201c;may,&#x201d; &#x201c;will,&#x201d; &#x201c;should,&#x201d; &#x201c;expects,&#x201d; &#x201c;plans,&#x201d; &#x201c;anticipates,&#x201d; &#x201c;could,&#x201d; &#x201c;intends,&#x201d; &#x201c;target,&#x201d; &#x201c;projects,&#x201d; &#x201c;contemplates,&#x201d; &#x201c;believes,&#x201d; &#x201c;estimates,&#x201d; &#x201c;predicts,&#x201d; &#x201c;potential&#x201d; or &#x201c;continue&#x201d; or the negative of these words or other similar terms or expressions that concern our expectations, strategy, plans or intentions. Forward-looking statements contained in this prospectus supplement and the accompanying base prospectus and the documents incorporated by reference herein and therein may include, but are not limited to, statements about:

&#x2022;
risks and uncertainties associated with our research and development activities, including our clinical trials and preclinical studies;
&#x2022;
the timing or likelihood of regulatory filings and approvals or of alternative regulatory pathways for our drug candidates;
&#x2022;
the potential market opportunities for commercializing our drug candidates;
&#x2022;
our expectations regarding the potential market size and the size of the patient populations for our drug candidates, if approved for commercial use, and our ability to serve such markets;
&#x2022;
estimates of our expenses, future revenue, capital requirements and our needs for additional financing;
&#x2022;
our ability to develop, acquire and advance our drug candidates into, and successfully complete, clinical trials and preclinical studies, and obtain regulatory approvals;
&#x2022;
the implementation of our business model and strategic plans for our business and drug candidates;
&#x2022;
the initiation, cost, timing, progress and results of future and current preclinical studies and clinical trials, and our research and development programs;
&#x2022;
new product candidates;
&#x2022;
the terms of future licensing arrangements, and whether we can enter into such arrangements at all;
&#x2022;
timing and receipt, or payments, of licensing and milestone revenues, if any;
&#x2022;
the scope of protection we are able to establish and maintain for intellectual property rights covering our drug candidates, and our ability to operate our business without infringing the intellectual property rights of others;
&#x2022;
regulatory developments in the United States and foreign countries;
&#x2022;
the performance of our third-party suppliers and manufacturers;
&#x2022;
our ability to maintain and establish collaborations or obtain additional funding;
&#x2022;
the success of competing therapies that are currently or may become available;
&#x2022;
our future financial performance;
&#x2022;
developments and projections relating to our competitors and our industry;

S-20

&#x2022;
our expectations regarding the completion of, and anticipated use of proceeds from, this offering and the concurrent common stock offering; and
&#x2022;
other risks and uncertainties, including those listed in the section titled &#x201c;Risk Factors.&#x201d;

We caution you that the forward-looking statements highlighted above do not encompass all of the forward-looking statements made in this prospectus supplement or the accompanying base prospectus or in the documents incorporated by reference herein and therein.

We have based the forward-looking statements contained in this prospectus supplement and the accompanying base prospectus and in the documents incorporated by reference herein and therein primarily on our current expectations and projections about future events and trends that we believe may affect our business, financial condition, results of operations and prospects. The outcomes of the events described in these forward-looking statements are subject to risks, uncertainties and other factors that could cause actual results and experience to differ from those projected, including, but not limited to, the risk factors described herein and the risk factors set forth in Part I - Item 1A, &#x201c;Risk Factors&#x201d;, in our Annual Report on Form 10-K for the year ended December 31, 2025, as filed with the SEC on February 11, 2026, in our Quarterly Report on Form 10-Q for the quarter ended March 31, 2026, as filed with the SEC on April 30, 2026 and in our Quarterly Report on Form 10-Q for the quarter ended June 30, 2026, as filed with the SEC on July 29, 2026 and elsewhere in the documents incorporated by reference into this prospectus supplement and the accompanying base prospectus. Moreover, we operate in a very competitive and challenging environment. New risks and uncertainties emerge from time to time, and it is not possible for us to predict all risks and uncertainties that could have an impact on the forward-looking statements contained in this prospectus supplement and the accompanying base prospectus and in the documents incorporated by reference herein and therein. We cannot assure you that the results, events and circumstances reflected in the forward-looking statements will be achieved or occur, and actual results, events or circumstances could differ materially from those described in the forward-looking statements.

The forward-looking statements contained in this prospectus supplement and the accompanying base prospectus and in the documents incorporated by reference herein and therein relate only to events as of the date on which the statements are made. We do not undertake any obligation to release publicly any revisions to such forward-looking statements to reflect events or circumstances after the date of this prospectus supplement or to reflect the occurrence of unanticipated events. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements and you should not place undue reliance on our forward-looking statements. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, joint ventures, other strategic transactions or investments we may make.

S-21

Market and Industry Data

This prospectus supplement and the accompanying base prospectus and the information incorporated by reference herein and therein contain statistical data, estimates, forecasts, projections and other information concerning our industry, our business and the markets for certain diseases, including data regarding the estimated size of those markets and the incidence and prevalence of certain medical conditions. Information that is based on statistical data, estimates, forecasts, projections, market research or similar methodologies is inherently subject to uncertainties and actual events or circumstances may differ materially from events and circumstances reflected in this information. Unless otherwise expressly stated, we obtained this industry, business, market and other data from reports, research surveys, medical and general publications, government data, studies and similar data prepared by market research firms and other third parties. These third parties may, in the future, alter the manner in which they conduct surveys and studies regarding the markets in which we operate our business. The market and other estimates included in this prospectus supplement and the accompanying base prospectus and the information incorporated by reference herein and therein, as they relate to projections, involve numerous assumptions, are subject to risks and uncertainties, and are subject to change based on various factors, including those discussed in the section of this prospectus supplement and the accompanying base prospectus titled &#x201c;Risk Factors&#x201d; and in the other information contained or incorporated by reference herein and therein.

S-22

Use of Proceeds

We estimate that the net proceeds to us from this offering will be approximately $ million (or approximately $ million if the underwriters exercise in full their option to purchase additional notes), after deducting the underwriting discounts and commissions and our estimated offering expenses. We intend to use the net proceeds from this offering, together with the net proceeds from the concurrent common stock offering, if it is consummated, for the continued clinical development, advancement and commercialization of our VK2735 program, the continued clinical development and advancement of our VK3019 program and for other general research and development, working capital and general corporate purposes. We may also use a portion of the net proceeds to acquire or invest in other businesses, products and technologies that are complementary to our own, although we have no current plans, commitments or arrangements to do so.

The amounts and timing of our use of the net proceeds from this offering and, if it is consummated, the concurrent common stock offering, will depend on a number of factors, such as the timing and progress of our research and development efforts, the timing and progress of any partnering and commercialization efforts, technological advances and the competitive environment for our products. As of the date of this prospectus supplement, we cannot specify with certainty all of the particular uses for the net proceeds to be received upon the completion of this offering and, if it is consummated, the concurrent common stock offering. Additionally, our management will have broad discretion in the timing and application of these proceeds. Pending application of the net proceeds as described above, we intend to invest the proceeds of this offering in money market funds, certificates of deposit and corporate debt securities.

S-23

Capitalization

The following table presents our cash and cash equivalents and our capitalization as of June 30, 2026:

&#x2022;
on an actual basis;
&#x2022;
on an as adjusted basis to give effect to the issuance and sale of $ aggregate principal amount of the notes we are offering, after deducting the underwriting discounts and commissions and our estimated offering expenses; and
&#x2022;
on a pro forma as adjusted basis to give further effect to the issuance and sale of our common stock in the concurrent common stock offering (assuming no exercise of the option of the underwriters of the concurrent common stock offering to purchase additional shares of our common stock), after deducting the underwriting discounts and commissions and our estimated offering expenses, assuming the concurrent common stock offering is consummated.

The information in the table below is illustrative only, and our capitalization following the completion of this offering and the concurrent common stock offering, if it is completed, will depend on the final terms of the offerings. Moreover, because the completion of this offering is not contingent on the completion of the concurrent common stock offering, you should not assume that the concurrent common stock offering, as reflected in the pro forma as adjusted column in the table below, will take place.

This table should be read in conjunction with the other information included or incorporated by reference in this prospectus supplement, including our consolidated financial statements and related notes.

As of June 30, 2026

Actual

As adjusted

Pro forma

as adjusted

(In thousands, except share and per share data)

Cash and cash equivalents

$125,750

$

$

Debt:

Principal amount of % convertible senior notes due 2032 we are offering(1)

$&#x2014;

$ __

$

Total debt

&#x2014;

Stockholders&#x2019; equity:

Preferred stock, $0.00001 par value per share; 10,000,000 shares authorized, no shares outstanding, actual, as adjusted and pro forma as adjusted

&#x2014;

&#x2014;

&#x2014;

Common stock, $0.00001 par value per share; 300,000,000 shares authorized; 116,652,937 shares outstanding, actual and as adjusted; shares outstanding, pro forma as adjusted

1

1

Additional paid-in capital

1,543,362

1,543,362

Accumulated deficit

(1,133,893)

(1,133,893)

(1,133,893)

Accumulated other comprehensive loss

(1,153)

(1,153)

(1,153)

Total stockholders&#x2019; equity

408,317

408,317

Total capitalization

$408,317

$

$

S-24

&#x2014;&#x2014;&#x2014;&#x2014;&#x2014;

(1)
The amounts shown in the table above for the notes we are offering represent their principal amount. However, we expect that the initial liability carrying amount of the notes for accounting purposes will be recorded net of issuance costs, which will be treated as a debt discount for accounting purposes and amortized into interest expense over the term of the notes. As a result of this amortization, the interest expense that we expect to recognize for the notes for accounting purposes will be greater than the cash interest payments we will pay on the notes, which will result in lower reported net income or larger reported net loss.

S-25

Description of Notes

We will issue the notes under an indenture (the &#x201c;base indenture&#x201d;), to be dated as of the initial closing date of this offering, between us and U.S. Bank Trust Company, National Association, as trustee (the &#x201c;trustee&#x201d;), as supplemented by a supplemental indenture (the base indenture, as so supplemented, the &#x201c;indenture&#x201d;), to be dated as of the initial closing date of this offering, between us and the trustee.

The following is a summary of certain provisions of the notes and the indenture. It is only a summary and is not complete. We qualify this summary by referring you to the indenture and the notes, because they, and not this summary, define your rights as a holder of the notes. We will provide you with a copy of the indenture, which includes the form of the notes, as provided under the caption &#x201c;Where You Can Find Additional Information.&#x201d; In addition, the indenture and the notes will be deemed to include certain terms that are made a part of the indenture and the notes pursuant to the Trust Indenture Act of 1939, as amended (the &#x201c;Trust Indenture Act&#x201d;).

This &#x201c;Description of Notes&#x201d; section supplements and, to the extent inconsistent therewith, supersedes the information in the accompanying prospectus under the caption &#x201c;Description of Debt Securities.&#x201d;

Certain terms used in this summary are defined below under the caption &#x201c;&#x2014;Definitions.&#x201d; Certain other terms used in this summary are defined in the indenture.

In this section, references to (i) &#x201c;we,&#x201d; &#x201c;us&#x201d; and &#x201c;our&#x201d; refer to Viking Therapeutics, Inc. only and not to any of its subsidiaries; and (ii) any &#x201c;note&#x201d; refer to any authorized denomination of a note, unless the context requires otherwise.

Generally

The notes will:

&#x2022;
be our senior, unsecured obligations;
&#x2022;
initially be limited to an aggregate principal amount of $ (or $ , if the underwriters exercise in full their option to purchase additional notes);
&#x2022;
bear interest from, and including, , 2026, at an annual rate of %, payable semi-annually in arrears on April 15 and October 15 of each year, beginning on April 15, 2027;
&#x2022;
bear special interest in the circumstances described below under the caption &#x201c;&#x2014;Events of Default&#x2014;Special Interest as Sole Remedy for Certain Reporting Defaults&#x201d;;
&#x2022;
mature on October 15, 2032, unless earlier repurchased, redeemed or converted;
&#x2022;
be redeemable, in whole or in part (subject to certain limitations), at our option, at any time, and from time to time, on or after October 22, 2029 and on or before the 25th &#x201c;scheduled trading day&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) immediately before the maturity date, at a cash redemption price equal to the principal amount of the notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date (subject to the right of noteholders on a regular record date to receive the related interest payment), but only if the &#x201c;last reported sale price&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) per share of our common stock exceeds 130% of the &#x201c;conversion price&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) for a specified period of time, as described below under the caption &#x201c;&#x2014;Optional Redemption&#x2014;Provisional Redemption&#x201d;;
&#x2022;
be redeemable, in whole and not in part, at our option, at any time, if the principal amount of the notes then outstanding is less than 15% of the aggregate principal amount of the notes issued in this offering (including any additional notes issued pursuant to any exercise of the underwriters&#x2019; option to purchase additional notes), at a cash redemption price equal to the principal amount of the notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date (subject to the right of noteholders on a regular record date to receive the related interest payment), as described below under the caption &#x201c;&#x2014;Optional Redemption&#x2014;Cleanup Redemption&#x201d;;

S-26

&#x2022;
be subject to repurchase by us at the noteholders&#x2019; option if a &#x201c;fundamental change&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) occurs, at a cash repurchase price equal to the principal amount of the notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date (subject to the right of noteholders on a regular record date to receive the related interest payment), as described, and subject to the limited exceptions set forth, below under the caption &#x201c;&#x2014;Fundamental Change Permits Noteholders to Require Us to Repurchase Notes&#x201d;;
&#x2022;
be convertible, at the noteholders&#x2019; option, into cash, shares of our common stock or a combination of cash and shares of our common stock (together with cash in lieu of any fractional share, if applicable), at our election, based on an initial conversion rate of shares per $1,000 principal amount of notes (which represents an initial conversion price of approximately $ per share), under the conditions, and subject to the adjustments, described below under the caption &#x201c;&#x2014;Conversion Rights&#x201d;;
&#x2022;
be issued in principal amount denominations of $1,000 or any integral multiple of $1,000 in excess thereof, which we refer to as an &#x201c;authorized denomination&#x201d;; and
&#x2022;
initially be represented by one or more registered notes in global form, but may, in certain circumstances, be exchanged for notes in definitive form, as described below under the caption &#x201c;&#x2014;Book Entry, Settlement and Clearance.&#x201d;

The indenture will not contain any financial covenants and will not limit us or our subsidiaries from incurring additional indebtedness, paying dividends or issuing or repurchasing any securities. Except to the extent described below under the captions &#x201c;&#x2014;Conversion Rights&#x2014;Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change,&#x201d; &#x201c;&#x2014;Fundamental Change Permits Noteholders to Require Us to Repurchase Notes&#x201d; and &#x201c;&#x2014;Consolidation, Merger and Asset Sale,&#x201d; the indenture will not contain any provisions designed to protect noteholders upon a highly leveraged transaction involving us or a decline in our credit rating as a result of a recapitalization, takeover, highly leveraged transaction or other restructuring involving us.

Without the consent of any noteholder, we may issue additional notes under the indenture with the same terms as the notes we are offering (except for certain differences, such as the date as of which interest begins to accrue on, and the first interest payment date for, such additional notes). However, such additional notes (and any notes that have been resold after they have been purchased or otherwise acquired by us or our subsidiaries) must be identified by a separate CUSIP number or by no CUSIP number if they are not fungible with other notes we issue under the indenture for purposes of federal income tax or federal securities laws or, if applicable, the &#x201c;depositary procedures&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;).

We do not intend to list the notes on any securities exchange or include them in any automated inter-dealer quotation system.

Absent manifest error, a person in whose name a note is registered on the registrar&#x2019;s books will be considered to be the holder of that note for all purposes, and only registered noteholders (which, in the case of notes held through DTC, will initially be DTC&#x2019;s nominee, Cede & Co.) will have rights under the indenture as noteholders.

Subject to applicable law, we or our subsidiaries may directly or indirectly repurchase notes in the open market, in negotiated transactions or otherwise (in each case without delivering prior notice to any noteholder), whether through private or public tender or exchange offers, cash-settled swaps or other cash-settled derivatives. Any notes that we or our subsidiaries have purchased or otherwise acquired will be deemed to remain outstanding until such time as we deliver them to the trustee for cancellation. However, subject to the terms of the indenture, notes that we or any of our affiliates own will be deemed not to be outstanding for purposes of determining whether the noteholders have concurred in any direction, waiver or consent.

Payments on the Notes

For purposes of the notes, the description below under this section titled &#x201c;&#x2014;Payments on the Notes&#x201d; supersedes, in its entirety, the information in the accompanying prospectus under the caption &#x201c;Description of Debt Securities&#x2014;Regarding Payments and Paying Agents.&#x201d;

S-27

We will pay (or cause the paying agent to pay) the principal of, and interest on, any global note by wire transfer of immediately available funds. We will pay (or cause the paying agent to pay) the principal of, and interest on, any physical note as follows:

&#x2022;
if the principal amount of such note is at least $5.0 million (or such lower amount as we may choose in our sole and absolute discretion) and the holder of such note entitled to such payment has delivered to the paying agent or the trustee, no later than the time set forth below, a written request to receive payment by wire transfer to an account of such holder within the United States, by wire transfer of immediately available funds to such account; and
&#x2022;
in all other cases, by check mailed to the address of such holder set forth in the note register.

To be timely, a written request referred to in the first bullet point above must be delivered no later than the &#x201c;close of business&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) on the following date: (i) with respect to the payment of any interest due on an interest payment date, the immediately preceding regular record date; and (ii) with respect to any other payment, the date that is 15 calendar days immediately before the date such payment is due.

If the due date for a payment on a note is not a &#x201c;business day&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;), then such payment may be made on the immediately following business day with the same force and effect as if such payment were made on that due date, and no interest will accrue on such payment as a result of the related delay. Solely for purposes of the immediately preceding sentence, a day on which the applicable place of payment is authorized or required by law or executive order to close or be closed will be deemed not to be a &#x201c;business day.&#x201d;

Registrar, Paying Agent and Conversion Agent

For purposes of the notes, the description below under this section titled &#x201c;&#x2014;Registrar, Paying Agent and Conversion Agent&#x201d; supersedes, in its entirety, the information in the accompanying prospectus under the caption &#x201c;Description of Debt Securities&#x2014;Regarding Payments and Paying Agents.&#x201d;

We will maintain one or more offices or agencies in the continental United States where notes may be presented for registration of transfer or for exchange, payment and conversion, which we refer to as the &#x201c;registrar,&#x201d; &#x201c;paying agent&#x201d; and &#x201c;conversion agent,&#x201d; respectively. We have appointed the trustee as the initial registrar, paying agent and conversion agent and its office in the United States as a place where notes may be presented for payment. However, without prior notice to the noteholders, we may change the registrar, paying agent and conversion agent and we or any of our subsidiaries may choose to act in that capacity as well (except that the registrar, paying agent or conversion agent with respect to any global note must at all times be a person that is eligible to act in that capacity under the depositary procedures).

Transfers and Exchanges

For purposes of the notes, the description below under this section titled &#x201c;&#x2014;Transfers and Exchanges&#x201d; supersedes, in its entirety, the information in the accompanying prospectus under the caption &#x201c;Description of Debt Securities&#x2014;Transfer and Exchange.&#x201d;

A noteholder may transfer or exchange its notes at the office of the registrar in accordance with the indenture. We, the trustee and the registrar may require the noteholder to, among other things, deliver appropriate endorsements or transfer instruments, and such certificates or other documentation or evidence as we or they may reasonably require to determine that such transfer or exchange complies with applicable securities laws. We, the trustee and the registrar may refuse to register the transfer or exchange of any note that is subject to conversion, redemption or required repurchase.

Interest

The notes will bear cash interest at an annual rate of % (which we refer to as the &#x201c;stated interest&#x201d;), payable semi-annually in arrears on April 15 and October 15 of each year, beginning on April 15, 2027, to the noteholders of record

S-28

of the notes as of the close of business on the immediately preceding April 1 and October 1, respectively. Interest will accrue from, and including, the last date to which interest has been paid or duly provided for (or, if no interest has been paid or duly provided for, from, and including, the date the notes are initially issued) to, but excluding, the next interest payment date. Interest will be computed on the basis of a 360-day year comprised of twelve 30-day months.

In addition to the stated interest on the notes referred to above, special interest will accrue on the notes in the circumstances described below under the caption &#x201c;&#x2014;Events of Default&#x2014;Special Interest as Sole Remedy for Certain Reporting Defaults.&#x201d; All references in this prospectus supplement to interest on the notes include any special interest and default interest (as described below under the caption &#x201c;&#x2014;Events of Default&#x2014;Default Interest&#x201d;) payable on the notes, unless the context requires otherwise.

If the first date on which any special interest begins to accrue on any global note is on or after the fifth business day before a regular record date and before the next interest payment date, then, notwithstanding anything to the contrary, the amount thereof accruing in respect of the period from, and including, such first date to, but excluding, such interest payment date will not be payable on such interest payment date but will instead be deemed to accrue (without duplication) entirely on such interest payment date and be payable on the immediately succeeding interest payment date (and, for the avoidance of doubt, no interest will accrue as a result of the related delay).

Ranking

The notes will be our senior, unsecured obligations and will be:

&#x2022;
equal in right of payment with our existing and future senior, unsecured indebtedness;
&#x2022;
senior in right of payment to our existing and future indebtedness that is expressly subordinated to the notes;
&#x2022;
effectively subordinated to our existing and future secured indebtedness, to the extent of the value of the collateral securing that indebtedness; and
&#x2022;
structurally subordinated to all existing and future indebtedness and other liabilities, including trade payables, and (to the extent we are not a holder thereof) preferred equity, if any, of our subsidiaries.

The indenture will not prohibit us from incurring additional indebtedness, including secured indebtedness, which would be effectively senior to the notes to the extent of the value of the collateral securing that indebtedness, or indebtedness that would rank equal in right of payment with the notes. The indenture will also not prohibit our subsidiaries from incurring any additional indebtedness or other liabilities that would be structurally senior to our obligations under the notes.

In the event of our bankruptcy, liquidation, reorganization or other winding up, our assets that secure any indebtedness will not be available to make payments under the notes unless all of that indebtedness is first paid in full. In the event of the bankruptcy, liquidation, reorganization or other winding up of any of our subsidiaries, we, as a common equity holder of that subsidiary, and, therefore, the noteholders, will rank behind that subsidiary&#x2019;s creditors, including that subsidiary&#x2019;s trade creditors, and (to the extent we are not a holder thereof) that subsidiary&#x2019;s preferred equity holders. Even if we were a creditor of any of our subsidiaries, our rights as a creditor would be effectively subordinated to any security interest of others in the assets of that subsidiary, to the extent of the value of those assets, and would be subordinated to any indebtedness of that subsidiary that is senior in right of payment to that held by us.

Our subsidiaries will have no obligations under the notes. The ability of our subsidiaries to pay dividends or make other payments to us is restricted by, among other things, corporate and other laws and by agreements to which our subsidiaries may become a party. Accordingly, we may be unable to gain access to the cash flow or assets of our subsidiaries to enable us to make payments on the notes.

As of June 30, 2026, excluding our subsidiaries , we had no indebtedness for borrowed money, and our subsidiaries had approximately $79.8 million of indebtedness and other liabilities.

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See &#x201c;Risk Factors&#x2014;The notes will be effectively subordinated to our existing and future secured indebtedness and structurally subordinated to the liabilities of our subsidiaries.&#x201d;

Optional Redemption

We may not redeem the notes at our option at any time before October 22, 2029, except pursuant to the provisions described below under the caption &#x201c;&#x2014;Cleanup Redemption.&#x201d;

Provisional Redemption

Subject to the terms of the indenture, we have the right, at our election, to redeem all, or any portion in an authorized denomination, of the notes, at any time, and from time to time, on a redemption date on or after October 22, 2029 and on or before the 25th scheduled trading day immediately before the maturity date, for cash, but only if the last reported sale price per share of our common stock exceeds 130% of the conversion price on (i) each of at least 20 &#x201c;trading days&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;), whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we send the related redemption notice; and (ii) the trading day immediately before the date we send such notice. We refer to a redemption pursuant to the provision described in the preceding sentence as a &#x201c;provisional redemption.&#x201d; However, we will not call less than all of the outstanding notes for provisional redemption unless the excess of the principal amount of notes outstanding as of the time we send the related redemption notice over the aggregate principal amount of notes set forth in such notice as being subject to provisional redemption is at least $100.0 million. In addition, calling any note for provisional redemption will constitute a &#x201c;make-whole fundamental change&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) with respect to that note, in which case the conversion rate applicable to the conversion of that note will be increased in certain circumstances if it is converted after it is called for provisional redemption. If we elect to redeem less than all of the outstanding notes pursuant to a provisional redemption, then the provisional redemption will not constitute a make-whole fundamental change with respect to the notes not called for provisional redemption, and holders of the notes not called for provisional redemption will not be entitled to an increased conversion rate for such notes as described above on account of the provisional redemption, except to the limited extent described further below.

Cleanup Redemption

Subject to the terms of the indenture, we have the right, at our election, to redeem all, but not less than all, of the notes, at any time, for cash, but only if the principal amount of the notes outstanding at the time we send the related redemption notice is less than 15% of the aggregate principal amount of the notes issued in this offering (including any additional notes issued pursuant to any exercise of the underwriters&#x2019; option to purchase additional notes). We refer to a redemption pursuant to the provision described in the preceding sentence as a &#x201c;cleanup redemption.&#x201d; In addition, calling any notes for cleanup redemption will constitute a make-whole fundamental change, which may result in a temporary increase to the conversion rate.

Redemption Date

The redemption date will be a business day of our choosing that is no more than 50, nor less than 30, scheduled trading days after the date we send the related redemption notice, as described below. However, if, in accordance with the provisions described below under the caption &#x201c;&#x2014;Conversion Rights&#x2014;Settlement Upon Conversion&#x2014;Settlement Method,&#x201d; we elect to settle all conversions with a conversion date that occurs on or after the date we send such redemption notice and on or before the second business day immediately before the related redemption date by physical settlement, then we may instead elect to choose a redemption date that is a business day no more than 60, nor less than 15, calendar days after the date we send such redemption notice.

Redemption Price

The redemption price for any note called for redemption will be the principal amount of such note plus accrued and unpaid interest on such note to, but excluding, the redemption date. However, if the redemption date is after a regular record date and on or before the next interest payment date, then (i) the holder of such note at the close of business on such regular record date will be entitled, notwithstanding such redemption, to receive, on or, at our election, before such interest payment date, the unpaid interest that would have accrued on such note to, but excluding, such interest

S-30

payment date; and (ii) the redemption price will not include accrued and unpaid interest on such note to, but excluding, such redemption date.

Redemption Notice

We will send to each applicable noteholder notice of the redemption containing certain information set forth in the indenture, including the redemption price and the redemption date.

Certain Provisions Applicable to Partial Redemptions

If only a portion of a note is subject to redemption and that note is converted in part, then the converted portion of that note will be deemed to be from the portion of that note that was subject to redemption.

If we elect to redeem less than all of the outstanding notes pursuant to a provisional redemption, and the holder of any note, or any owner of a beneficial interest in any global note, is reasonably not able to determine, before the close of business on the 27th scheduled trading day (or, if, as described above, we irrevocably elect physical settlement for all conversions with a conversion date that occurs on or after the date we send the related redemption notice and on or before the second business day immediately before the related redemption date, the 10th calendar day) immediately before the relevant redemption date, whether such note or beneficial interest, as applicable, is to be redeemed pursuant to such redemption, then such holder or owner, as applicable, will be entitled to convert such note or beneficial interest, as applicable, at any time before the close of business on the second business day immediately before such redemption date, and each such conversion will be deemed to be of a note called for such redemption for purposes of these redemption provisions and the provisions described below under the captions &#x201c;&#x2014;Conversion Rights&#x2014;When the Notes May Be Converted&#x2014;Conversion Upon Redemption&#x201d; and &#x201c;&#x2014;Conversion Rights&#x2014;Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change.&#x201d; For the avoidance of doubt, each reference in this prospectus supplement to (i) any note that is called for redemption (or similar language) includes any note that is deemed to be called for redemption pursuant to the provision described in this paragraph; and (ii) any note that is not called for redemption (or similar language) excludes any note that is deemed to be called for redemption pursuant to the provision described in this paragraph.

Redemption Prohibited in Certain Circumstances

Notwithstanding anything to the contrary above, we may not redeem any notes if the principal amount of the notes has been accelerated and such acceleration has not been rescinded on or before the redemption date (including as a result of the payment of the related redemption price and any related interest described above on the redemption date).

Conversion Rights

Generally

Noteholders will have the right to convert their notes (or any portion of a note in an authorized denomination), in the circumstances described below, into consideration that consists, at our election, of cash, shares of our common stock or a combination of cash and shares of our common stock (together with cash in lieu of any fractional share, if applicable), based on an initial conversion rate of shares per $1,000 principal amount of notes (which represents an initial conversion price of approximately $ per share).

Noteholders may convert their notes only in the circumstances described below under the caption &#x201c;&#x2014;When the Notes May Be Converted.&#x201d;

Treatment of Interest Upon Conversion

We will not adjust the conversion rate to account for any accrued and unpaid interest on any note being converted, and, except as described below, our delivery of the consideration due in respect of the conversion will be deemed to fully satisfy and discharge our obligation to pay the principal of, and accrued and unpaid interest, if any, on, such note to, but excluding, the &#x201c;conversion date&#x201d; (as defined below under the caption &#x201c;&#x2014;Conversion Procedures&#x201d;). As a result, except as described below, any accrued and unpaid interest on a converted note will be deemed to be paid in full rather

S-31

than cancelled, extinguished or forfeited. In addition, if the consideration due upon conversion consists of both cash and shares of our common stock, then accrued and unpaid interest that is deemed to be paid therewith will be deemed to be paid first out of such cash.

Notwithstanding anything to the contrary above, if the conversion date of a note is after a regular record date and before the next interest payment date, then:

&#x2022;
the holder of such note at the close of business on such regular record date will be entitled, notwithstanding such conversion, to receive, on or, at our election, before such interest payment date, the unpaid interest that would have accrued on such note to, but excluding, such interest payment date; and
&#x2022;
the noteholder surrendering such note for conversion must deliver, at the time it surrenders such note, an amount of cash equal to the amount of such interest.

However, such noteholder need not deliver such cash:

&#x2022;
if we have specified a redemption date that is after such regular record date and on or before the second business day immediately after such interest payment date;
&#x2022;
if such conversion date occurs after the regular record date immediately before the maturity date;
&#x2022;
if we have specified a &#x201c;fundamental change repurchase date&#x201d; (as defined below under the caption &#x201c;&#x2014;Fundamental Change Permits Noteholders to Require Us to Repurchase Notes&#x201d;) that is after such regular record date and on or before the business day immediately after such interest payment date; or
&#x2022;
to the extent of any special interest, overdue interest or interest that has accrued on any overdue interest.

Accordingly, for the avoidance of doubt, all noteholders as of the close of business on the regular record date immediately before the maturity date, or immediately before any redemption date or fundamental change repurchase date referred to in the bullets in the preceding paragraph, will receive the full interest payment that would have been due on the maturity date or other applicable interest payment date regardless of whether their notes have been converted after such regular record date.

When the Notes May Be Converted

Noteholders may convert their notes only in the circumstances set forth below. However, in no event may notes be converted after the close of business on the second scheduled trading day immediately before the maturity date.

Conversion Upon Satisfaction of Common Stock Sale Price Condition

A noteholder may convert its notes during any calendar quarter (and only during such calendar quarter) commencing after the calendar quarter ending on December 31, 2026, if the last reported sale price per share of our common stock exceeds 130% of the conversion price for each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter.

Conversion Upon Satisfaction of Note Trading Price Condition

A noteholder may convert its notes during the five consecutive business days immediately after any 10 consecutive trading day period (such 10 consecutive trading day period, the &#x201c;measurement period&#x201d;) if the &#x201c;trading price&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) per $1,000 principal amount of notes, as determined following a request by a noteholder in accordance with the procedures described below, for each trading day of the measurement period was less than 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day. We refer to this condition as the &#x201c;trading price condition.&#x201d;

The trading price will be determined by the bid solicitation agent as described below and in the definition of &#x201c;trading price.&#x201d; The bid solicitation agent (if not us) will have no obligation to determine the trading price of the notes unless

S-32

we have requested such determination in writing, and we will have no obligation to make such request (or seek bids ourselves) unless a noteholder provides us with reasonable evidence that the trading price per $1,000 principal amount of notes would be less than 98% of the product of the last reported sale price per share of our common stock and the conversion rate. If a noteholder provides such evidence, then we will instruct the bid solicitation agent to (or, if we are acting as the bid solicitation agent, we will) determine the trading price of the notes beginning on the next trading day and on each successive trading day until the trading price per $1,000 principal amount of notes is greater than or equal to 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day. If the trading price condition has been met as described above, then we will notify the noteholders of the same. If, on any trading day after the trading price condition has been met as described above, the trading price per $1,000 principal amount of notes is greater than or equal to 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day, then we will notify the noteholders of the same.

We will act as the initial bid solicitation agent. However, we may change the bid solicitation agent, and we may appoint any of our subsidiaries to act in that capacity as well, without prior notice to the noteholders.

Conversion Upon Specified Corporate Events

Certain Distributions

If, before July 15, 2032, we elect to:

&#x2022;
distribute, to all or substantially all holders of our common stock, any rights, options or warrants (other than rights issued pursuant to a stockholder rights plan, so long as such rights have not separated from our common stock and are not exercisable until the occurrence of a triggering event, except that such rights will be deemed to be distributed under this bullet point upon their separation from our common stock or upon the occurrence of such triggering event) entitling them, for a period of not more than 60 calendar days after the date such distribution is first publicly announced, to subscribe for or purchase shares of our common stock at a price per share that is less than the average of the last reported sale prices per share of our common stock for the 10 consecutive trading days ending on, and including, the trading day immediately before the date such distribution is announced (determined in accordance with the provisions described in the third paragraph of clause (2) under the heading &#x201c;&#x2014;Conversion Rate Adjustments&#x2014;Generally&#x201d; below); or
&#x2022;
distribute, to all or substantially all holders of our common stock, assets or securities of ours or rights to purchase our securities, which distribution per share of our common stock has a value, as reasonably determined by us in good faith, exceeding 10% of the last reported sale price per share of our common stock on the trading day immediately before the date such distribution is announced,

then, in either case, we will send notice of such distribution, and of the related right to convert notes, to noteholders at least 30 scheduled trading days before the &#x201c;ex-dividend date&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) for such distribution (or, if later in the case of any such separation of rights issued pursuant to a stockholder rights plan or the occurrence of any such triggering event under a stockholder rights plan, as soon as reasonably practicable after we become aware that such separation or triggering event has occurred or will occur). However, if we are then otherwise permitted to settle conversions by physical settlement (and, for the avoidance of doubt, we have not elected (or been deemed to have elected) another settlement method to apply, including pursuant to the provision described in the third sentence under the caption &#x201c;&#x2014;Settlement Upon Conversion&#x2014;Settlement Method&#x201d; below), then we may instead elect to provide such notice at least 10 scheduled trading days before such ex-dividend date. In that event, we will be required to settle all conversions with a conversion date occurring on or after the date we provide such notice and on or before the business day immediately before the ex-dividend date for such distribution (or any earlier announcement by us that such distribution will not take place) by physical settlement, and we will describe the same in the notice. Once we have sent such notice, noteholders may convert their notes at any time until the earlier of the close of business on the business day immediately before such ex-dividend date and our announcement that such distribution will not take place. However, the notes will not become convertible on account of such distribution (but we will still be required to send notice of such distribution as described above) if each noteholder participates, at the same time and on the same terms as holders of our common stock, and solely by virtue of being a noteholder, in such distribution without having to convert such noteholder&#x2019;s notes and as if such noteholder held a number of shares of

S-33

our common stock equal to the product of (i) the conversion rate in effect on the record date for such distribution; and (ii) the aggregate principal amount (expressed in thousands) of notes held by such noteholder on such record date.

Certain Corporate Events

If a fundamental change, make-whole fundamental change (other than a make-whole fundamental change pursuant to clause (ii) of the definition thereof) or &#x201c;common stock change event&#x201d; (as defined below under the caption &#x201c;&#x2014;Effect of Common Stock Change Event&#x201d;) occurs (other than a merger or other business combination transaction that is effected solely to change our jurisdiction of incorporation and that does not constitute a fundamental change or a make-whole fundamental change), then, in each case, noteholders may convert their notes at any time from, and including, the effective date of such transaction or event to, and including, the 35th trading day after such effective date (or, if such transaction or event also constitutes a fundamental change (other than an &#x201c;exempted fundamental change,&#x201d; as defined below under the caption &#x201c;&#x2014;Fundamental Change Permits Noteholders to Require Us to Repurchase Notes&#x2014;No Repurchase Right in Certain Circumstances&#x201d;), to, but excluding, the related fundamental change repurchase date). No later than the second business day after such effective date, we will send notice to the noteholders of such transaction or event, such effective date and the related right to convert notes. If we do not provide such notice by the second business day after the effective date, then the last day on which the notes are convertible will be extended by the number of business days from, and including, the second business day after the effective date to, but excluding, the date we provide the notice.

Conversion Upon Redemption

If we call any note for redemption, then the holder of such note may convert such note at any time before the close of business on the second business day immediately before the related redemption date (or, if we fail to pay the redemption price due on such redemption date in full, at any time until such time as we pay such redemption price in full).

Conversions During Free Convertibility Period

A noteholder may convert its notes at any time from, and including, July 15, 2032 until the close of business on the second scheduled trading day immediately before the maturity date.

Conversion Procedures

To convert a beneficial interest in a global note, the owner of the beneficial interest must:

&#x2022;
comply with the depositary procedures for converting the beneficial interest (at which time such conversion will become irrevocable unless we, in our sole and absolute discretion, agree to permit the owner of the beneficial interest to withdraw such conversion and such withdrawal is reasonably feasible pursuant to the applicable procedures of the depositary);
&#x2022;
if applicable, pay any interest payable on the next interest payment date, as described above under the caption &#x201c;&#x2014;Treatment of Interest Upon Conversion&#x201d;; and
&#x2022;
if applicable, pay any documentary or other taxes as described below.

To convert all or a portion of a physical note, the holder of such note must:

&#x2022;
complete, manually sign and deliver to the conversion agent the conversion notice attached to such note or a facsimile of such conversion notice;
&#x2022;
deliver such note to the conversion agent (at which time such conversion will become irrevocable unless we, in our sole and absolute discretion, agree to permit the holder of such note to withdraw such conversion);
&#x2022;
furnish any endorsements and transfer documents that we or the conversion agent may require;

S-34

&#x2022;
if applicable, pay any interest payable on the next interest payment date, as described above under the caption &#x201c;&#x2014;Treatment of Interest Upon Conversion&#x201d;; and
&#x2022;
if applicable, pay any documentary or other taxes as described below.

Notes may be surrendered for conversion only after the &#x201c;open of business&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) and before the close of business on a day that is a business day.

We will pay any documentary, stamp or similar issue or transfer tax or duty due on the issue or delivery of any shares of our common stock upon conversion. However, if any tax or duty is due because the converting noteholder requests those shares to be registered in a name other than such noteholder&#x2019;s name, then such noteholder must pay such tax or duty.

We refer to the first business day on which the requirements described above to convert a note are satisfied as the &#x201c;conversion date,&#x201d; subject to the provision described in the last sentence under the caption &#x201c;&#x2014;Settlement Upon Conversion&#x2014;Delivery of the Conversion Consideration.&#x201d;

If a noteholder has validly delivered a &#x201c;fundamental change repurchase notice&#x201d; (as defined below under the caption &#x201c;&#x2014;Fundamental Change Permits Noteholders to Require Us to Repurchase Notes&#x201d;) with respect to a note, then such note may not be converted, except to the extent (i) such notice is withdrawn in accordance with the procedures described below; or (ii) we fail to pay the related fundamental change repurchase price for such note when required (or a third party fails to make such payment in lieu of us in accordance with the provisions described below under the caption &#x201c;&#x2014;Fundamental Change Permits Noteholders to Require Us to Repurchase Notes&#x2014;Repurchase by Third Party&#x201d;).

Settlement Upon Conversion

Generally

Upon conversion, we may choose to pay or deliver, as applicable, either cash (&#x201c;cash settlement&#x201d;), shares of our common stock (&#x201c;physical settlement&#x201d;) or a combination of cash and shares of our common stock (&#x201c;combination settlement&#x201d;), as described below. We refer to each of these settlement methods as a &#x201c;settlement method.&#x201d; If cash settlement or combination settlement applies to a conversion, then the consideration due will be determined based on the conversion rate, the &#x201c;daily VWAPs&#x201d; per share of our common stock over an &#x201c;observation period&#x201d; consisting of 25 consecutive &#x201c;VWAP trading days&#x201d; and, in the case of combination settlement, the &#x201c;specified dollar amount&#x201d; (as those terms are defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) that applies to the conversion.

Settlement Method

We will have the right, as described below, to elect the settlement method applicable to the conversion of any notes. Except as described below, we must use the same settlement method for all conversions with the same conversion date, but we will not be obligated to use the same settlement method for conversions with different conversion dates. All conversions with a conversion date that occurs on or after July 15, 2032 will be settled using the same settlement method, and we will send notice of such settlement method to noteholders no later than the open of business on July 15, 2032. If we elect a settlement method for a conversion with a conversion date that occurs before July 15, 2032, then we will send notice of such settlement method to the converting noteholder no later than the close of business on the business day immediately after the conversion date. However, as described above under the captions &#x201c;&#x2014;Optional Redemption&#x2014;Redemption Date&#x201d; and &#x201c;&#x2014;When the Notes May Be Converted&#x2014;Conversion Upon Specified Corporate Events&#x2014;Certain Distributions,&#x201d; we may in certain circumstances elect that physical settlement apply to all conversions with a conversion date occurring during the periods referred to under those captions. Notwithstanding anything to the contrary described above, if we call any notes for redemption, then (i) we will specify in the related redemption notice (and, in the case of a redemption of less than all outstanding notes, in a notice simultaneously sent to all holders of notes not called for redemption) the settlement method that will apply to all conversions with a conversion date that occurs on or after the date we send such redemption notice and on or before the second business day before the related redemption date; and (ii) if the related redemption date is on or after July 15, 2032, then such

S-35

settlement method must be the same settlement method that applies to all conversions with a conversion date that occurs on or after July 15, 2032.

If we do not timely elect a settlement method with respect to any conversion, then we will be deemed to have elected the &#x201c;default settlement method&#x201d; (as defined below). If we timely elect combination settlement with respect to a conversion but do not timely notify the converting noteholder of the applicable specified dollar amount, then the specified dollar amount for such conversion will be deemed to be $1,000 per $1,000 principal amount of notes. For the avoidance of doubt, our failure to timely elect a settlement method or specify the applicable specified dollar amount will not constitute a default or event of default under the indenture.

The &#x201c;default settlement method&#x201d; will initially be physical settlement. However, we may, from time to time, change the default settlement method, to any settlement method that we are then permitted to elect, by sending notice of the new default settlement method to the noteholders. In addition, we may, by notice to the noteholders, elect to irrevocably fix the settlement method or to irrevocably eliminate any one or more (but not all) settlement methods (including eliminating combination settlement with a particular specified dollar amount or range of specified dollar amounts). If we make such an irrevocable election, then such election will apply to all note conversions with a conversion date that is on or after the date we send such notice and we will, if needed, simultaneously change the default settlement method to a settlement method that is consistent with such irrevocable election. However, in all cases, no such irrevocable election will affect any settlement method theretofore elected (or deemed to be elected) with respect to any note pursuant to the indenture. For the avoidance of doubt, such an irrevocable election, if made, will be effective without the need to amend the indenture or the notes, including pursuant to the provisions described in the seventh bullet point of the third paragraph under the caption &#x201c;&#x2014;Modification and Amendment&#x201d; below. However, we may nonetheless choose to execute such an amendment at our option.

If we change the default settlement method or irrevocably fix the settlement method pursuant to the provisions described above, then we will, substantially concurrently, either post the default settlement method or fixed settlement method, as applicable, on our website or disclose the same in a current report on Form 8-K (or any successor form) that is filed with, or furnished to, the SEC.

Consideration Due Upon Conversion

Subject to the other provisions described in this section, the consideration due upon conversion of each $1,000 principal amount of a note will be as follows:

&#x2022;
if physical settlement applies, a number of shares of our common stock equal to the conversion rate in effect on the conversion date for such conversion;
&#x2022;
if cash settlement applies, cash in an amount equal to the sum of the &#x201c;daily conversion values&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) for each VWAP trading day in the observation period for such conversion; or
&#x2022;
if combination settlement applies, (i) a number of shares of our common stock equal to the sum of the &#x201c;daily share amounts&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) for each VWAP trading day in the observation period for such conversion; and (ii) an amount of cash equal to the sum of the &#x201c;daily cash amounts&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) for each VWAP trading day in such observation period.

However, in lieu of delivering any fractional share of our common stock otherwise due upon conversion, we will pay cash based on (i) the daily VWAP on the applicable conversion date (or, if such conversion date is not a VWAP trading day, the immediately preceding VWAP trading day), in the case of physical settlement; or (ii) the daily VWAP on the last VWAP trading day of the applicable observation period, in the case of combination settlement.

If a noteholder converts more than one note on a conversion date, then the consideration due upon such conversion will (in the case of any global note, to the extent permitted by, and practicable under, the depositary procedures) be computed based on the total principal amount of notes converted on such conversion date by that noteholder.

S-36

Delivery of the Conversion Consideration

Except as described below under the captions &#x201c;&#x2014;Conversion Rate Adjustments&#x201d; and &#x201c;&#x2014;Effect of Common Stock Change Event,&#x201d; we will pay or deliver, as applicable, the consideration due upon conversion as follows: (i) if cash settlement or combination settlement applies, on or before the second business day immediately after the last VWAP trading day of the observation period for such conversion; and (ii) if physical settlement applies, on or before the second business day immediately after the conversion date for such conversion. However, if physical settlement applies to the conversion of any note with a conversion date that is after the regular record date immediately before the maturity date, or of any note that has been called for redemption with a conversion date that occurs during the 15 calendar days preceding the related redemption date, then, solely for purposes of such conversion, (i) we will pay or deliver, as applicable, the consideration due upon such conversion on or before the maturity date (or, if the maturity date is not a business day, the next business day), in the case of a conversion of any note with a conversion date that is after the regular record date immediately before the maturity date, or the related redemption date, in the case of a conversion of any note that has been called for redemption with a conversion date that occurs during the 15 calendar days preceding such redemption date; and (ii) the conversion date will instead be deemed to be the second business day immediately before the date referred to in clause (i).

When Converting Noteholders Become Stockholders of Record

The person in whose name any share of our common stock is issuable upon conversion of any note will be deemed to become the holder of record of that share as of the close of business on (i) the conversion date for such conversion, in the case of physical settlement; or (ii) the last VWAP trading day of the observation period for such conversion, in the case of combination settlement.

Conversion Rate Adjustments

Generally

The conversion rate will be adjusted for the events described below. However, we are not required to adjust the conversion rate for these events (other than a stock split or combination or a tender or exchange offer) if each noteholder participates, at the same time and on the same terms as holders of our common stock, and solely by virtue of being a holder of notes, in such transaction or event without having to convert such noteholder&#x2019;s notes and as if such noteholder held a number of shares of our common stock equal to the product of (i) the conversion rate in effect on the related record date; and (ii) the aggregate principal amount (expressed in thousands) of notes held by such noteholder on such date.

(1)
Stock Dividends, Splits and Combinations. If we issue solely shares of our common stock as a dividend or distribution on all or substantially all shares of our common stock, or if we effect a stock split or a stock combination of our common stock (in each case excluding an issuance solely pursuant to a common stock change event, as to which the provisions described below under the caption &#x201c;&#x2014;Effect of Common Stock Change Event&#x201d; will apply), then the conversion rate will be adjusted based on the following formula:

where:

CR0 = the conversion rate in effect immediately before the open of business on the ex-dividend date for such dividend or distribution, or immediately before the open of business on the effective date of such stock split or stock combination, as applicable;

CR1 = the conversion rate in effect immediately after the open of business on such ex-dividend date or effective date, as applicable;

S-37

OS0 = the number of shares of our common stock outstanding immediately before the open of business on such ex-dividend date or effective date, as applicable, without giving effect to such dividend, distribution, stock split or stock combination; and

OS1 = the number of shares of our common stock outstanding immediately after giving effect to such dividend, distribution, stock split or stock combination.

If any dividend, distribution, stock split or stock combination of the type described in this paragraph (1) is declared or announced, but not so paid or made, then the conversion rate will be readjusted, effective as of the date our board of directors determines not to pay such dividend or distribution or to effect such stock split or stock combination, to the conversion rate that would then be in effect had such dividend, distribution, stock split or stock combination not been declared or announced.

(2)
Rights, Options and Warrants. If we distribute, to all or substantially all holders of our common stock, rights, options or warrants (other than rights issued or otherwise distributed pursuant to a stockholder rights plan, as to which the provisions described below in paragraph (3)(a) and under the caption &#x201c;&#x2014;Stockholder Rights Plans&#x201d; will apply) entitling such holders, for a period of not more than 60 calendar days after the date such distribution is first publicly announced, to subscribe for or purchase shares of our common stock at a price per share that is less than the average of the last reported sale prices per share of our common stock for the 10 consecutive trading days ending on, and including, the trading day immediately before the date such distribution is announced, then the conversion rate will be increased based on the following formula:

where:

CR0 = the conversion rate in effect immediately before the open of business on the ex-dividend date for such distribution;

CR1 = the conversion rate in effect immediately after the open of business on such ex-dividend date;

OS = the number of shares of our common stock outstanding immediately before the open of business on such ex-dividend date;

X = the total number of shares of our common stock issuable pursuant to such rights, options or warrants; and

Y = a number of shares of our common stock obtained by dividing (x) the aggregate price payable to exercise such rights, options or warrants by (y) the average of the last reported sale prices per share of our common stock for the 10 consecutive trading days ending on, and including, the trading day immediately before the date such distribution is announced.

To the extent such rights, options or warrants are not so distributed, the conversion rate will be readjusted to the conversion rate that would then be in effect had the increase to the conversion rate for such distribution been made on the basis of only the rights, options or warrants, if any, actually distributed. In addition, to the extent that shares of our common stock are not delivered after the expiration of such rights, options or warrants (including as a result of such rights, options or warrants not being exercised), the conversion rate will be readjusted to the conversion rate that would then be in effect had the increase to the conversion rate for such distribution been made on the basis of delivery of only the number of shares of our common stock actually delivered upon exercise of such rights, options or warrants.

S-38

For purposes of this paragraph (2) and the provisions described above under the caption &#x201c;&#x2014;When the Notes May Be Converted&#x2014;Conversion Upon Specified Corporate Events&#x2014;Certain Distributions,&#x201d; in determining whether any rights, options or warrants entitle holders of our common stock to subscribe for or purchase shares of our common stock at a price per share that is less than the average of the last reported sale prices per share of our common stock for the 10 consecutive trading days ending on, and including, the trading day immediately before the date the distribution of such rights, options or warrants is announced, and in determining the aggregate price payable to exercise such rights, options or warrants, there will be taken into account any consideration we receive for such rights, options or warrants and any amount payable on exercise thereof, with the value of such consideration, if not cash, to be determined by us in good faith and in a commercially reasonable manner.

(3)
Spin-Offs and Other Distributed Property.
(a)
Distributions Other Than Spin-Offs. If we distribute shares of our &#x201c;capital stock&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;), evidences of our indebtedness or other assets or property of ours, or rights, options or warrants to acquire our capital stock or other securities, to all or substantially all holders of our common stock, excluding:
&#x2022;
dividends, distributions, rights, options or warrants for which an adjustment to the conversion rate is required (or would be required without regard to the &#x201c;deferral exception&#x201d; (as defined below under the caption &#x201c;&#x2014;The Deferral Exception&#x201d;)) pursuant to paragraph (1) or (2) above;
&#x2022;
dividends or distributions paid exclusively in cash for which an adjustment to the conversion rate is required (or would be required without regard to the deferral exception) pursuant to paragraph (4) below;
&#x2022;
rights issued or otherwise distributed pursuant to a stockholder rights plan, except to the extent provided below under the caption &#x201c;&#x2014;Stockholder Rights Plans&#x201d;;
&#x2022;
spin-offs for which an adjustment to the conversion rate is required (or would be required without regard to the deferral exception) pursuant to paragraph (3)(b) below;
&#x2022;
a distribution solely pursuant to a tender offer or exchange offer for shares of our common stock, as to which the provisions described below in paragraph (5) will apply; and
&#x2022;
a distribution solely pursuant to a common stock change event, as to which the provisions described below under the caption &#x201c;&#x2014;Effect of Common Stock Change Event&#x201d; will apply,

then the conversion rate will be increased based on the following formula:

where:

CR0 = the conversion rate in effect immediately before the open of business on the ex-dividend date for such distribution;

CR1 = the conversion rate in effect immediately after the open of business on such ex-dividend date;

SP = the average of the last reported sale prices per share of our common stock for the 10 consecutive trading days ending on, and including, the trading day immediately before such ex-dividend date; and

S-39

FMV = the fair market value (as determined by us in good faith and in a commercially reasonable manner), as of such ex-dividend date, of the shares of capital stock, evidences of indebtedness, assets, property, rights, options or warrants distributed per share of our common stock pursuant to such distribution.

However, if FMV is equal to or greater than SP, then, in lieu of the foregoing adjustment to the conversion rate, each noteholder will receive, for each $1,000 principal amount of notes held by such noteholder on the record date for such distribution, at the same time and on the same terms as holders of our common stock, and without having to convert its notes, the amount and kind of shares of capital stock, evidences of indebtedness, assets, property, rights, options or warrants that such noteholder would have received in such distribution if such noteholder had owned, on such record date, a number of shares of our common stock equal to the conversion rate in effect on such record date.

To the extent such distribution is not so paid or made, the conversion rate will be readjusted to the conversion rate that would then be in effect had the adjustment been made on the basis of only the distribution, if any, actually made or paid.

(b)
Spin-Offs. If we distribute or dividend shares of capital stock of any class or series, or similar equity interests, of or relating to an &#x201c;affiliate&#x201d; or &#x201c;subsidiary&#x201d; (as those terms are defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) or other business unit of ours to all or substantially all holders of our common stock (other than solely pursuant to (x) a common stock change event, as to which the provisions described below under the caption &#x201c;&#x2014;Effect of Common Stock Change Event&#x201d; will apply; or (y) a tender offer or exchange offer for shares of our common stock, as to which the provisions described below in paragraph (5) will apply), and such capital stock or equity interests are listed or quoted (or will be listed or quoted upon the consummation of the transaction) on a U.S. national securities exchange (a &#x201c;spin-off&#x201d;), then the conversion rate will be increased based on the following formula:

where:

CR0 = the conversion rate in effect immediately before the close of business on the last trading day of the &#x201c;spin-off valuation period&#x201d; (as defined below) for such spin-off;

CR1 = the conversion rate in effect immediately after the close of business on the last trading day of the spin-off valuation period;

FMV = the product of (x) the average of the last reported sale prices per share or unit of the capital stock or equity interests distributed in such spin-off over the 10 consecutive trading day period (the &#x201c;spin-off valuation period&#x201d;) beginning on, and including, the ex-dividend date for such spin-off (such average to be determined as if references to our common stock in the definitions of &#x201c;last reported sale price,&#x201d; &#x201c;trading day&#x201d; and &#x201c;market disruption event&#x201d; were instead references to such capital stock or equity interests); and (y) the number of shares or units of such capital stock or equity interests distributed per share of our common stock in such spin-off; and

SP = the average of the last reported sale prices per share of our common stock for each trading day in the spin-off valuation period.

S-40

Notwithstanding anything to the contrary, (i) if any VWAP trading day of the observation period for a note whose conversion will be settled pursuant to cash settlement or combination settlement occurs during the spin-off valuation period for such spin-off, then, solely for purposes of determining the conversion rate for such VWAP trading day for such conversion, such spin-off valuation period will be deemed to consist of the trading days occurring in the period from, and including, the ex-dividend date for such spin-off to, and including, such VWAP trading day; and (ii) if the conversion date for a note whose conversion will be settled pursuant to physical settlement occurs during the spin-off valuation period for such spin-off, then, solely for purposes of determining the consideration due in respect of such conversion, such spin-off valuation period will be deemed to consist of the trading days occurring in the period from, and including, the ex-dividend date for such spin-off to, and including, such conversion date.

To the extent any dividend or distribution of the type described above in this paragraph (3)(b) is declared but not made or paid, the conversion rate will be readjusted to the conversion rate that would then be in effect had the adjustment been made on the basis of only the dividend or distribution, if any, actually made or paid.

(4)
Cash Dividends or Distributions. If any cash dividend or distribution is made to all or substantially all holders of our common stock, then the conversion rate will be increased based on the following formula:

where:

CR0 = the conversion rate in effect immediately before the open of business on the ex-dividend date for such dividend or distribution;

CR1 = the conversion rate in effect immediately after the open of business on such ex-dividend date;

SP = the last reported sale price per share of our common stock on the trading day immediately before such ex-dividend date; and

D = the cash amount distributed per share of our common stock in such dividend or distribution.

However, if D is equal to or greater than SP, then, in lieu of the foregoing adjustment to the conversion rate, each noteholder will receive, for each $1,000 principal amount of notes held by such noteholder on the record date for such dividend or distribution, at the same time and on the same terms as holders of our common stock, and without having to convert its notes, the amount of cash that such noteholder would have received in such dividend or distribution if such noteholder had owned, on such record date, a number of shares of our common stock equal to the conversion rate in effect on such record date. To the extent such dividend or distribution is declared but not made or paid, the conversion rate will be readjusted to the conversion rate that would then be in effect had the adjustment been made on the basis of only the dividend or distribution, if any, actually made or paid.

(5)
Tender Offers or Exchange Offers. If we or any of our subsidiaries makes a payment in respect of a tender offer or exchange offer for shares of our common stock (other than solely pursuant to an odd-lot tender offer pursuant to Rule 13e-4(h)(5) under the Exchange Act), and the value (determined as of the expiration time by us in good faith and in a commercially reasonable manner) of the cash and other consideration paid or payable per share of our common stock in such tender or exchange offer exceeds the last reported sale price per share of our common stock on the trading day immediately after the last date (the &#x201c;expiration date&#x201d;) on which tenders or exchanges may be made pursuant to such tender or exchange offer (as it may be amended),

S-41

then the conversion rate will be increased based on the following formula:

where:

CR0 = the conversion rate in effect immediately before the close of business on the last trading day of the &#x201c;tender/exchange offer valuation period&#x201d; (as defined below) for such tender or exchange offer;

CR1 = the conversion rate in effect immediately after the close of business on the last trading day of the tender/exchange offer valuation period;

AC = the aggregate value (determined as of the time (the &#x201c;expiration time&#x201d;) such tender or exchange offer expires by us in good faith and in a commercially reasonable manner) of all cash and other consideration paid or payable for shares of our common stock purchased or exchanged in such tender or exchange offer;

OS0 = the number of shares of our common stock outstanding immediately before the expiration time (including all shares of our common stock accepted for purchase or exchange in such tender or exchange offer);

OS1 = the number of shares of our common stock outstanding immediately after the expiration time (excluding all shares of our common stock accepted for purchase or exchange in such tender or exchange offer); and

SP = the average of the last reported sale prices per share of our common stock over the 10 consecutive trading day period (the &#x201c;tender/exchange offer valuation period&#x201d;) beginning on, and including, the trading day immediately after the expiration date;

provided, however, that the conversion rate will in no event be adjusted down pursuant to the provisions described in this paragraph (5), except to the extent provided in the immediately following paragraph. Notwithstanding anything to the contrary, (i) if any VWAP trading day of the observation period for a note whose conversion will be settled pursuant to cash settlement or combination settlement occurs during the tender/exchange offer valuation period for such tender or exchange offer, then, solely for purposes of determining the conversion rate for such VWAP trading day for such conversion, such tender/exchange offer valuation period will be deemed to consist of the trading days occurring in the period from, and including, the trading day immediately after the expiration date for such tender or exchange offer to, and including, such VWAP trading day; and (ii) if the conversion date for a note whose conversion will be settled pursuant to physical settlement occurs during the tender/exchange offer valuation period for such tender or exchange offer, then, solely for purposes of determining the consideration due in respect of such conversion, such tender/exchange offer valuation period will be deemed to consist of the trading days occurring in the period from, and including, the trading day immediately after the expiration date to, and including, such conversion date.

To the extent such tender or exchange offer is announced but not consummated (including as a result of being precluded from consummating such tender or exchange offer under applicable law), or any purchases or exchanges of shares of our common stock in such tender or exchange offer are rescinded, the conversion rate will be readjusted to the conversion rate that would then be in effect had the adjustment been made on the basis of only the purchases or exchanges of shares of our common stock, if any, actually made, and not rescinded, in such tender or exchange offer.

S-42

We will not be required to adjust the conversion rate except as described above or below under the caption &#x201c;&#x2014;Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change.&#x201d; Without limiting the foregoing, we will not be required to adjust the conversion rate on account of:

&#x2022;
except as described above, the sale of shares of our common stock for a purchase price that is less than the market price per share of our common stock or less than the conversion price;
&#x2022;
the issuance of any shares of our common stock pursuant to any present or future plan providing for the reinvestment of dividends or interest payable on our securities and the investment of additional optional amounts in shares of our common stock under any such plan;
&#x2022;
the issuance of any shares of our common stock or options or rights to purchase shares of our common stock pursuant to any present or future employee, director or consultant benefit or incentive plan or program (including any employee stock purchase plan) of, or assumed by, us or any of our subsidiaries;
&#x2022;
the issuance of any shares of our common stock pursuant to any option, warrant, right or convertible, exercisable or exchangeable security of ours outstanding as of the date we first issue the notes;
&#x2022;
a third-party tender offer, other than a tender offer that is subject to paragraph (5) above;
&#x2022;
the repurchase of any shares of our common stock pursuant to an open-market share repurchase program or other buyback transaction, including structured or derivative transactions such as accelerated share repurchase transactions or similar forward derivatives, in each case that is not subject to paragraph (5) above;
&#x2022;
solely a change in the par value of our common stock; or
&#x2022;
accrued and unpaid interest on the notes.

Notice of Conversion Rate Adjustments

Upon the effectiveness of any adjustment to the conversion rate pursuant to the provisions described above under the caption &#x201c;&#x2014;Conversion Rate Adjustments&#x2014;Generally,&#x201d; we will promptly send notice to the noteholders containing (i) a brief description of the transaction or other event on account of which such adjustment was made; (ii) the conversion rate in effect immediately after such adjustment; and (iii) the effective time of such adjustment.

Voluntary Conversion Rate Increases

To the extent permitted by law and applicable stock exchange rules, we, from time to time, may (but are not required to) increase the conversion rate by any amount if (i) our board of directors determines that such increase is in our best interest or that such increase is advisable to avoid or diminish any income tax imposed on holders of our common stock or rights to purchase our common stock as a result of any dividend or distribution of shares (or rights to acquire shares) of our common stock or any similar event; (ii) such increase is in effect for a period of at least 20 business days; and (iii) such increase is irrevocable during such period.

Tax Considerations

A holder or beneficial owner of the notes may, in some circumstances, including a cash distribution or dividend on our common stock, be deemed to have received a distribution that is subject to U.S. federal income tax as a result of an adjustment or the non-occurrence of an adjustment to the conversion rate. Applicable withholding taxes (including backup withholding) due on such distribution or otherwise due with respect to the notes may be withheld from interest and payments upon conversion, repurchase, redemption or maturity of the notes. In addition, if any withholding taxes (including backup withholding) are paid on behalf of a holder or beneficial owner, then those withholding taxes may be withheld from or set off against payments of cash or the delivery of shares of our common stock, if any, in respect of the notes (or, in some circumstances, any payments on our common stock) or proceeds of any sale, exchange or other disposition of such notes received by, or other funds or assets of, that holder or beneficial owner. For a discussion of the U.S. federal income tax treatment of an adjustment to the conversion rate, see &#x201c;Material U.S. Federal Income Tax Considerations.&#x201d;

S-43

The Deferral Exception

If an adjustment to the conversion rate otherwise required by the indenture would result in a change of less than 1% to the conversion rate, then we may, at our election, defer and carry forward such adjustment, except that all such deferred adjustments must be given effect immediately upon the earliest of the following: (i) when all such deferred adjustments would, had they not been so deferred and carried forward, result in a change of at least 1% to the conversion rate; (ii) the conversion date of, or any VWAP trading day of an observation period for, any note; (iii) the date a fundamental change or make-whole fundamental change occurs; (iv) the date we call any notes for redemption; and (v) July 15, 2032. We refer to our ability to defer adjustments as described above as the &#x201c;deferral exception.&#x201d;

Special Provisions for Adjustments that Are Not Yet Effective and Where Converting Noteholders Participate in the Relevant Transaction or Event

Notwithstanding anything to the contrary, if:

&#x2022;
a note is to be converted pursuant to physical settlement or combination settlement;
&#x2022;
the record date, effective date or expiration time for any event that requires an adjustment to the conversion rate pursuant to the provisions described above under the caption &#x201c;&#x2014;Conversion Rate Adjustments&#x2014;Generally&#x201d; has occurred on or before the conversion date for such conversion (in the case of physical settlement) or on or before any VWAP trading day in the observation period for such conversion (in the case of combination settlement), but an adjustment to the conversion rate for such event has not yet become effective as of such conversion date or VWAP trading day, as applicable;
&#x2022;
the consideration due upon such conversion includes any whole shares of our common stock (in the case of physical settlement) or due in respect of such VWAP trading day includes any whole or fractional shares of our common stock (in the case of combination settlement); and
&#x2022;
such shares are not entitled to participate in such event (because they were not held on the related record date or otherwise),

then, solely for purposes of such conversion, we will, without duplication, give effect to such adjustment on such conversion date (in the case of physical settlement) or such VWAP trading day (in the case of combination settlement). In such case, if the date we are otherwise required to deliver the consideration due upon such conversion is before the first date on which the amount of such adjustment can be determined, then we will delay the settlement of such conversion until the second business day after such first date.

Notwithstanding anything to the contrary, if:

&#x2022;
a conversion rate adjustment for any dividend or distribution becomes effective on any ex-dividend date pursuant to the provisions described above under the caption &#x201c;&#x2014;Conversion Rate Adjustments&#x2014;Generally&#x201d;;
&#x2022;
a note is to be converted pursuant to physical settlement or combination settlement;
&#x2022;
the conversion date for such conversion (in the case of physical settlement) or any VWAP trading day in the observation period for such conversion (in the case of combination settlement) occurs on or after such ex-dividend date and on or before the related record date;
&#x2022;
the consideration due upon such conversion includes any whole shares of our common stock (in the case of physical settlement) or due in respect of such VWAP trading day includes any whole or fractional shares of our common stock (in the case of combination settlement), in each case based on a conversion rate that is adjusted for such dividend or distribution; and
&#x2022;
such shares would be entitled to participate in such dividend or distribution,

S-44

then:

&#x2022;
in the case of physical settlement, such conversion rate adjustment will not be given effect for such conversion and the shares of our common stock issuable upon such conversion based on such unadjusted conversion rate will not be entitled to participate in such dividend or distribution, but there will be added, to the consideration otherwise due upon such conversion, the same kind and amount of consideration that would have been delivered in such dividend or distribution with respect to such shares had such shares been entitled to participate in such dividend or distribution; and
&#x2022;
in the case of combination settlement, the conversion rate adjustment relating to such ex-dividend date will be made for such conversion in respect of such VWAP trading day, but the shares of our common stock issuable with respect to such VWAP trading day based on such adjusted conversion rate will not be entitled to participate in such dividend or distribution.

Stockholder Rights Plans

If any shares of our common stock are to be issued upon conversion of any note and, at the time of such conversion, we have in effect any stockholder rights plan, then the holder of that note will be entitled to receive, in addition to, and concurrently with the delivery of, the consideration otherwise due upon such conversion, the rights set forth in such stockholder rights plan, unless such rights have separated from our common stock at such time, in which case, and only in such case, the conversion rate will be adjusted pursuant to the provisions described above in paragraph (3)(a) under the caption &#x201c;&#x2014;Conversion Rate Adjustments&#x2014;Generally&#x201d; on account of such separation as if, at the time of such separation, we had made a distribution of the type referred to in such paragraph to all holders of our common stock, subject to potential readjustment pursuant to the provisions described in such paragraph. We currently do not have a stockholder rights plan.

Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change

Generally

If a make-whole fundamental change occurs and the conversion date for the conversion of a note occurs during the related &#x201c;make-whole fundamental change conversion period&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;), then, subject to the provisions described below, the conversion rate applicable to such conversion will be increased by a number of shares (the &#x201c;additional shares&#x201d;) set forth in the table below corresponding (after interpolation as described below) to the &#x201c;make-whole fundamental change effective date&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) and the &#x201c;stock price&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) of such make-whole fundamental change:

Stock Price

Make-Whole Fundamental Change Effective Date

$

$

$

$

$

$

$

$

, 2026

October 15, 2027

October 15, 2028

October 15, 2029

October 15, 2030

October 15, 2031

October 15, 2032

If such make-whole fundamental change effective date or stock price is not set forth in the table above, then:

&#x2022;
if such stock price is between two stock prices in the table above or the make-whole fundamental change effective date is between two dates in the table above, then the number of additional shares will be determined by straight-line interpolation between the numbers of additional shares set forth for the higher and lower stock prices in the table above or the earlier and later dates in the table above, based on a 365- or 366-day year, as applicable; and

S-45

&#x2022;
if the stock price is greater than $ (subject to adjustment in the same manner as the stock prices set forth in the column headings of the table above are adjusted, as described below under the caption &#x201c;&#x2014;Adjustment of Stock Prices and Number of Additional Shares&#x201d;), or less than $ (subject to adjustment in the same manner), per share, then no additional shares will be added to the conversion rate.

Notwithstanding anything to the contrary, in no event will the conversion rate be increased to an amount that exceeds shares of our common stock per $1,000 principal amount of notes, which amount is subject to adjustment in the same manner as, and at the same time and for the same events for which, the conversion rate is required to be adjusted pursuant to the provisions described above under the caption &#x201c;&#x2014;Conversion Rate Adjustments&#x2014;Generally.&#x201d;

For the avoidance of doubt, calling any notes for provisional redemption will constitute a make-whole fundamental change only with respect to the notes called for such redemption, and not with respect to the notes not called for such redemption. Accordingly, if we elect to redeem less than all of the outstanding notes pursuant to a provisional redemption, then holders of the notes not called for such redemption will not be entitled to an increased conversion rate for such notes as described above on account of such redemption, except to the limited extent described above under the caption &#x201c;&#x2014;Optional Redemption&#x2014;Certain Provisions Applicable to Partial Redemptions.&#x201d;

As set forth in the definition of &#x201c;make-whole fundamental change conversion period&#x201d; below under the caption &#x201c;&#x2014;Definitions,&#x201d; if the conversion date for the conversion of a note occurs during a make-whole fundamental change conversion period relating to both a make-whole fundamental change resulting from our calling notes for provisional redemption or cleanup redemption and another make-whole fundamental change, then, solely for purposes of that conversion, such conversion date will be deemed to occur only during the period relating to the make-whole fundamental change with the earlier make-whole fundamental change effective date. In that circumstance, the make-whole fundamental change with the later make-whole fundamental change effective date will be deemed not to occur for purposes of such conversion.

Adjustment of Stock Prices and Number of Additional Shares

The stock prices in the first row (i.e., the column headers) of the table above will be adjusted in the same manner as, and at the same time and for the same events for which, the conversion price is adjusted as a result of the operation of the provisions described above under the caption &#x201c;&#x2014;Conversion Rate Adjustments&#x2014;Generally.&#x201d; The numbers of additional shares in the table above will be adjusted in the same manner as, and at the same time and for the same events for which, the conversion rate is adjusted pursuant to the provisions described above under the caption &#x201c;&#x2014;Conversion Rate Adjustments&#x2014;Generally.&#x201d;

Notice of Make-Whole Fundamental Change

We will notify noteholders of each make-whole fundamental change in accordance with the provisions described above under the captions &#x201c;&#x2014;When the Notes May Be Converted&#x2014;Conversion Upon Specified Corporate Events&#x2014;Certain Corporate Events&#x201d; and &#x201c;&#x2014;Optional Redemption&#x2014;Redemption Notice.&#x201d;

Enforceability

Our obligation to increase the conversion rate as described above in connection with a make-whole fundamental change could be considered a penalty, in which case its enforceability would be subject to general principles of reasonableness and equitable remedies.

Effect of Common Stock Change Event

Generally

If there occurs any:

&#x2022;
recapitalization, reclassification or change of our common stock, other than (x) changes solely resulting from a subdivision or combination of our common stock, (y) a change only in par value or from par value to no

S-46

par value or no par value to par value or (z) stock splits and stock combinations that do not involve the issuance of any other series or class of securities;
&#x2022;
consolidation, merger, combination or binding or statutory share exchange involving us;
&#x2022;
sale, lease or other transfer of all or substantially all of the assets of us and our subsidiaries, taken as a whole, to any person; or
&#x2022;
other similar event,

and, as a result of which, our common stock is converted into, or is exchanged for, or represents solely the right to receive, other securities, cash or other property, or any combination of the foregoing (such an event, a &#x201c;common stock change event,&#x201d; and such other securities, cash or property, the &#x201c;reference property,&#x201d; and the amount and kind of reference property that a holder of one share of our common stock would be entitled to receive on account of such common stock change event (without giving effect to any arrangement not to issue or deliver a fractional portion of any security or other property), a &#x201c;reference property unit&#x201d;), then, notwithstanding anything to the contrary,

&#x2022;
from and after the effective time of such common stock change event, (i) the consideration due upon conversion of any note, and the conditions to any such conversion, will be determined in the same manner as if each reference to any number of shares of our common stock in the provisions described under this &#x201c;&#x2014;Conversion Rights&#x201d; section (or in any related definitions) were instead a reference to the same number of reference property units; (ii) for purposes of the redemption provisions described above under the caption &#x201c;&#x2014;Optional Redemption&#x2014;Provisional Redemption,&#x201d; each reference to any number of shares of our common stock in such provisions (or in any related definitions) will instead be deemed to be a reference to the same number of reference property units; and (iii) for purposes of the definitions of &#x201c;fundamental change&#x201d; and &#x201c;make-whole fundamental change,&#x201d; references to our &#x201c;common stock&#x201d; and &#x201c;common equity&#x201d; will be deemed to refer to the common equity (including depositary receipts representing common equity), if any, forming part of such reference property;
&#x2022;
if such reference property unit consists entirely of cash, then (i) each conversion of any note with a conversion date that occurs on or after the effective date of such common stock change event will be settled entirely in cash in an amount, per $1,000 principal amount of such note being converted, equal to the product of (x) the conversion rate in effect on such conversion date (including, for the avoidance of doubt, any increase to such conversion rate pursuant to the provisions described above under the caption &#x201c;&#x2014;Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change,&#x201d; if applicable); and (y) the amount of cash constituting such reference property unit; and (ii) we will settle each such conversion no later than the fifth business day after the relevant conversion date; and
&#x2022;
for these purposes, (i) the daily VWAP of any reference property unit or portion thereof that consists of a class of common equity securities will be determined by reference to the definition of &#x201c;daily VWAP,&#x201d; substituting, if applicable, the Bloomberg page for such class of securities in such definition; and (ii) the daily VWAP of any reference property unit or portion thereof that does not consist of a class of common equity securities, and the last reported sale price of any reference property unit or portion thereof that does not consist of a class of securities, will be the fair value of such reference property unit or portion thereof, as applicable, determined in good faith and in a commercially reasonable manner by us (or, in the case of cash denominated in U.S. dollars, the face amount thereof).

If the reference property consists of more than a single type of consideration to be determined based in part upon any form of stockholder election, then the composition of the reference property unit will be deemed to be the weighted average of the types and amounts of consideration actually received, per share of our common stock, by the holders of our common stock. We will notify the noteholders of such weighted average as soon as practicable after such determination is made.

We will not become a party to any common stock change event unless its terms are consistent with the provisions described under this &#x201c;&#x2014;Effect of Common Stock Change Event&#x201d; caption.

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Execution of Supplemental Indenture

At or before the effective time of the common stock change event, we and the resulting, surviving or transferee person (if not us) of such common stock change event (the &#x201c;successor person&#x201d;) will execute and deliver to the trustee a supplemental indenture that (i) provides for subsequent adjustments to the conversion rate in a manner consistent with the provisions described above; and (ii) contains such other provisions, if any, that we reasonably determine are appropriate to preserve the economic interests of the noteholders and to give effect to the provisions described above. If the reference property includes shares of stock or other securities or assets (other than cash) of a person other than the successor person, then such other person will also execute such supplemental indenture and such supplemental indenture will contain such additional provisions, if any, that we reasonably determine are appropriate to preserve the economic interests of noteholders.

However, no such supplemental indenture is required (but we may nonetheless choose to execute such a supplemental indenture at our option) if (i) we are the resulting, surviving or transferee person of such common stock change event; and (ii) the reference property of such common stock change event does not include consideration other than cash or our securities.

Notice of Common Stock Change Event

We will provide notice of each common stock change event to noteholders no later than the second business day after the effective date of the common stock change event.

Exchange in Lieu of Conversion

Notwithstanding anything to the contrary, and subject to the terms of the indenture, if a note is submitted for conversion, we may elect to arrange to have such note exchanged in lieu of conversion by a financial institution we designate. To make such election, we must send notice of such election to the holder of such note before the close of business on the business day immediately following the conversion date for such note, and we must arrange for the financial institution to deliver the consideration due upon such conversion in the same manner and at the same time as we would have been required to do so. We will remain responsible to deliver such consideration if the financial institution fails to timely deliver the same.

Equitable Adjustments to Prices

Whenever the indenture requires us to calculate the average of the last reported sale prices, or any function thereof, over a period of multiple days (including to calculate the stock price or an adjustment to the conversion rate), or to calculate daily VWAPs over an observation period, we will make appropriate adjustments, if any, to those calculations to account for any adjustment to the conversion rate pursuant to the provisions described above under the caption &#x201c;&#x2014;Conversion Rights&#x2014;Conversion Rate Adjustments&#x2014;Generally&#x201d; that becomes effective, or any event requiring such an adjustment to the conversion rate where the ex-dividend date or effective date, as applicable, of such event occurs, at any time during such period or observation period, as applicable.

Fundamental Change Permits Noteholders to Require Us to Repurchase Notes

For purposes of the notes, the description below under this section titled &#x201c;&#x2014;Fundamental Change Permits Noteholders to Require Us to Repurchase Notes&#x201d; supersedes, in its entirety, the information in the accompanying prospectus under the caption &#x201c;Description of Debt Securities&#x2014;No Protection in the Event of a Change of Control.&#x201d;

Generally

If a fundamental change occurs prior to the maturity date, then each noteholder will have the right (the &#x201c;fundamental change repurchase right&#x201d;) to require us to repurchase its notes (or any portion thereof in an authorized denomination) for cash on a date (the &#x201c;fundamental change repurchase date&#x201d;) of our choosing, which must be a business day that is no more than 35, nor less than 20, business days after the date we send the related fundamental change notice, as described below.

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The repurchase price (the &#x201c;fundamental change repurchase price&#x201d;) for a note tendered for repurchase will be the principal amount of such note plus accrued and unpaid interest on such note to, but excluding, the fundamental change repurchase date. However, if the fundamental change repurchase date is after a regular record date and on or before the next interest payment date, then (i) the holder of such note at the close of business on such regular record date will be entitled, notwithstanding such repurchase, to receive, on or, at our election, before such interest payment date, the unpaid interest that would have accrued on such note to, but excluding, such interest payment date; and (ii) the fundamental change repurchase price will not include accrued and unpaid interest on such note to, but excluding, the fundamental change repurchase date.

Notwithstanding anything to the contrary above, we may not repurchase any notes if the principal amount of the notes has been accelerated and such acceleration has not been rescinded on or before the fundamental change repurchase date (including as a result of the payment of the related fundamental change repurchase price and any related interest described above on the fundamental change repurchase date).

Notice of Fundamental Change

On or before the 20th calendar day after the effective date of a fundamental change, we will send to each noteholder notice of such fundamental change containing certain information set forth in the indenture, including the fundamental change repurchase date, the fundamental change repurchase price and the procedures noteholders must follow to tender their notes for repurchase.

Procedures to Exercise the Fundamental Change Repurchase Right

To exercise its fundamental change repurchase right with respect to a note, the holder thereof must deliver a notice (a &#x201c;fundamental change repurchase notice&#x201d;) to the paying agent before the close of business on the business day immediately before the related fundamental change repurchase date (or such later time as may be required by law).

The fundamental change repurchase notice must contain certain information set forth in the indenture, including the certificate number of any physical notes to be repurchased, or must otherwise comply with the depositary procedures in the case of a global note.

A noteholder that has delivered a fundamental change repurchase notice with respect to a note may withdraw that notice by delivering a withdrawal notice to the paying agent at any time before the close of business on the business day immediately before the fundamental change repurchase date. The withdrawal notice must contain certain information set forth in the indenture, including the certificate number of any physical notes with respect to which the withdrawal notice is being delivered, or must otherwise comply with the depositary procedures in the case of a global note.

Notes to be repurchased must be delivered to the paying agent (in the case of physical notes) or the depositary procedures must be complied with (in the case of global notes) for the holder of those notes to be entitled to receive the fundamental change repurchase price.

Compliance with Securities Laws

We will comply, in all material respects, with all federal and state securities laws in connection with a repurchase following a fundamental change (including complying with Rules 13e-4 and 14e-1 under the Exchange Act and filing any required Schedule TO, to the extent applicable) so as to permit effecting such repurchase in the manner described above. However, to the extent that our obligations to offer to repurchase and to repurchase notes pursuant to the provisions described above conflict with any law or regulation that is applicable to us and enacted after the date we initially issue the notes, our compliance with such law or regulation will not be considered to be a default of those obligations.

Repurchase by Third Party

Notwithstanding anything to the contrary, we will be deemed to satisfy our obligations to repurchase notes pursuant to the provisions described above if (i) one or more third parties conduct the repurchase offer and repurchase tendered

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notes in a manner that would have satisfied our obligations to do the same if conducted directly by us; and (ii) an owner of a beneficial interest in any note repurchased by such third party or parties will not receive a lesser amount (as a result of withholding or other similar taxes) than such owner would have received had we repurchased such note.

No Repurchase Right in Certain Circumstances

Notwithstanding anything to the contrary, we will not be required to send a fundamental change notice, or offer to repurchase or repurchase any notes, as described above, in connection with a common stock change event that constitutes a fundamental change pursuant to clause (ii)(2) of the definition thereof (regardless of whether such common stock change event also constitutes a fundamental change pursuant to any other clause of such definition), if:

&#x2022;
the reference property of such common stock change event consists entirely of cash in U.S. dollars;
&#x2022;
immediately after such fundamental change, the notes become convertible (pursuant to the provisions described above under the captions &#x201c;&#x2014;Conversion Rights&#x2014;Effect of Common Stock Change Event&#x201d; and, if applicable, &#x201c;&#x2014;Conversion Rights&#x2014;Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change&#x201d;) into consideration that consists solely of U.S. dollars in an amount per $1,000 principal amount of notes that equals or exceeds the fundamental change repurchase price per $1,000 principal amount of notes (calculated assuming that the same includes accrued and unpaid interest to, but excluding, the latest possible fundamental change repurchase date for such fundamental change); and
&#x2022;
we timely send the notice relating to such fundamental change required pursuant to the provisions described above under the caption &#x201c;&#x2014;Conversion Rights&#x2014;When the Notes May Be Converted&#x2014;Conversion Upon Specified Corporate Events&#x2014;Certain Corporate Events&#x201d; and include, in such notice, a statement that we are relying on the provisions described in this &#x201c;&#x2014;No Repurchase Right in Certain Circumstances&#x201d; section.

We refer to any fundamental change with respect to which, in accordance with the provisions described above, we do not offer to repurchase any notes as an &#x201c;exempted fundamental change.&#x201d;

Consolidation, Merger and Asset Sale

For purposes of the notes, the description below under this section titled &#x201c;&#x2014;Consolidation, Merger and Asset Sale&#x201d; supersedes, in its entirety, the information in the accompanying prospectus under the caption &#x201c;Description of Debt Securities&#x2014;Consolidation, Merger or Sale of Assets.&#x201d;

We will not consolidate with or merge with or into, or (directly, or indirectly through one or more of our subsidiaries) sell, lease or otherwise transfer, in one transaction or a series of transactions, all or substantially all of the assets of us and our subsidiaries, taken as a whole, to another person (a &#x201c;business combination event&#x201d;), unless:

&#x2022;
the resulting, surviving or transferee person is us or, if not us, is a &#x201c;qualified successor entity&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) (such qualified successor entity, the &#x201c;successor entity&#x201d;) duly organized and existing under the laws of the United States of America, any State thereof or the District of Columbia that expressly assumes (by executing and delivering to the trustee, at or before the effective time of such business combination event, a supplemental indenture) all of our obligations under the indenture and the notes; and
&#x2022;
immediately after giving effect to such business combination event, no &#x201c;default&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) will have occurred and be continuing.

At the effective time of a business combination event that complies with the provisions described above, the successor entity (if not us) will succeed to, and may exercise every right and power of, us under the indenture and the notes, and, except in the case of a lease, the predecessor company will be discharged from its obligations under the indenture and the notes.

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Notwithstanding anything to the contrary above, the provisions described above will not apply to any transfer of assets (other than by merger or consolidation) between or among us and any one or more of our &#x201c;wholly owned subsidiaries&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;).

The definition of &#x201c;business combination event&#x201d; includes a reference to &#x201c;all or substantially all&#x201d; of our and our subsidiaries&#x2019; assets. There is no precise, established definition of the phrase &#x201c;all or substantially all&#x201d; under applicable law. Accordingly, there may be uncertainty as to whether the provisions described above would apply to a sale, lease or transfer of less than all of our and our subsidiaries&#x2019; assets.

Events of Default

For purposes of the notes, the description below under this section titled &#x201c;&#x2014;Events of Default&#x201d; supersedes, in its entirety, the information in the accompanying prospectus under the caption &#x201c;Description of Debt Securities&#x2014;Events of Default.&#x201d;

Generally

An &#x201c;event of default&#x201d; means the occurrence of any of the following:

(1)
a default in the payment when due (whether at maturity, upon redemption or repurchase upon fundamental change or otherwise) of the principal of, or the redemption price or fundamental change repurchase price for, any note;
(2)
a default for 30 consecutive days in the payment when due of interest on any note;
(3)
our failure to deliver, when required by the indenture, a fundamental change notice or a notice pursuant to the provisions described above under the caption &#x201c;&#x2014;Conversion Rights&#x2014;When the Notes May Be Converted&#x2014;Conversion Upon Specified Corporate Events,&#x201d; if (in the case of any notice other than a notice pursuant to the provisions described above under the caption &#x201c;&#x2014;Conversion Rights&#x2014;When the Notes May Be Converted&#x2014;Conversion Upon Specified Corporate Events&#x2014;Certain Distributions&#x201d;) such failure is not cured within five days after its occurrence;
(4)
a default in our obligation to convert a note in accordance with the indenture upon the exercise of the conversion right with respect thereto, if such default is not cured within five days after its occurrence;
(5)
a default in our obligations described above under the caption &#x201c;&#x2014;Consolidation, Merger and Asset Sale&#x201d;;
(6)
a default in any of our obligations or agreements under the notes or under the indenture with respect to the notes (other than a default set forth in paragraphs (1), (2), (3), (4) or (5) above) where such default is not cured or waived within 60 days after notice to us by the trustee, or to us and the trustee by holders of at least 25% of the aggregate principal amount of notes then outstanding, which notice must specify such default, demand that it be remedied and state that such notice is a &#x201c;notice of default&#x201d;;
(7)
a default by us or any of our &#x201c;significant subsidiaries&#x201d; (as defined below under the caption &#x201c;&#x2014;Definitions&#x201d;) with respect to any one or more mortgages, agreements or other instruments under which there is outstanding, or by which there is secured or evidenced, any indebtedness for borrowed money with a principal amount of at least $30,000,000 (or its foreign currency equivalent) in the aggregate of us or any of our significant subsidiaries, whether such indebtedness exists as of the date we first issue the notes or is thereafter created, where such default:
&#x2022;
constitutes a failure to pay the principal of such indebtedness when due and payable at its stated maturity, upon required repurchase, upon declaration of acceleration or otherwise, in each case after the expiration of any applicable grace period; or
&#x2022;
results in such indebtedness becoming or being declared due and payable before its stated maturity,

in each case where such default is not cured or waived within 30 days after notice to us by the trustee or to us and the trustee by holders of at least 25% of the aggregate principal amount of notes then outstanding; and

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(8)
certain events of bankruptcy, insolvency and reorganization with respect to us or any of our significant subsidiaries.

Acceleration

If an event of default described in paragraph (8) above occurs with respect to us (and not solely with respect to a significant subsidiary of ours), then the principal amount of, and all accrued and unpaid interest on, all of the notes then outstanding will immediately become due and payable without any further action or notice by any person. If an event of default (other than an event of default described in paragraph (8) above with respect to us and not solely with respect to a significant subsidiary of ours) occurs and is continuing, then, except as described below under the caption &#x201c;&#x2014;Special Interest as Sole Remedy for Certain Reporting Defaults,&#x201d; the trustee, by notice to us, or noteholders of at least 25% of the aggregate principal amount of notes then outstanding, by notice to us and the trustee, may declare the principal amount of, and all accrued and unpaid interest on, all of the notes then outstanding to become due and payable immediately. For the avoidance of doubt, if such event of default is not continuing at the time such notice is provided (that is, such event of default has been cured or waived as of such time), then such notice will not be effective to cause such amounts to become due and payable immediately.

Noteholders of a majority in aggregate principal amount of the notes then outstanding, by notice to us and the trustee, may, on behalf of all noteholders, rescind any acceleration of the notes and its consequences if (i) such rescission would not conflict with any judgment or decree of a court of competent jurisdiction; and (ii) all existing events of default (except the non-payment of principal of, or interest on, the notes that has become due solely because of such acceleration) have been cured or waived. No such rescission will affect any subsequent default or impair any right consequent thereto.

If any portion of the amount payable on the notes upon acceleration is considered by a court to be unearned interest (through the allocation of the value of the instrument to the embedded warrant or otherwise), then the court could disallow recovery of any such portion.

Waiver of Past Defaults

A default that is (or, after notice, passage of time or both, would be) an event of default pursuant to paragraph (1), (2), (4) or (6) above (that, in the case of paragraph (6) only, results from a default under any covenant that cannot be amended without the consent of each affected noteholder) can be waived only with the consent of each affected noteholder. Each other default may be waived, on behalf of all noteholders, by noteholders of a majority in aggregate principal amount of the notes then outstanding.

Cure of Defaults; Ability to Cure or Waive Before Event of Default Occurs

For the avoidance of doubt, and without limiting the manner in which any default can be cured,

&#x2022;
a default consisting of a failure to send a notice in accordance with the terms of the indenture will be cured upon the sending of such notice;
&#x2022;
a default in making any payment on (or delivering any other consideration in respect of) any note will be cured upon the delivery, in accordance with the indenture, of such payment (or other consideration) together, if applicable, with &#x201c;default interest&#x201d; (as defined below under the caption &#x201c;&#x2014;Default Interest&#x201d;) thereon; and
&#x2022;
a default that is (or, after notice, passage of time or both, would be) a &#x201c;reporting event of default&#x201d; (as defined below under the caption &#x201c;&#x2014;Special Interest as Sole Remedy for Certain Reporting Defaults&#x201d;) will be cured upon the filing of the relevant report(s) giving rise to such default.

In addition, for the avoidance of doubt, if a default that is not an event of default is cured or waived before such default would have constituted an event of default, then no event of default will result from such default.

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Notice of Defaults

If a default occurs, then we will, within 30 days after its first occurrence, notify the trustee, setting forth what action we are taking or propose to take with respect thereto. However, we will not be required to provide such notification at any time after such default is cured or waived. We must also provide the trustee annually with a certificate as to whether any defaults have occurred or are continuing. If a default occurs and is continuing and is actually known to a responsible officer of the trustee, then the trustee must notify the noteholders of the same within 90 days after it occurs or, if it is not actually known to a responsible officer of the trustee at such time, promptly (and in any event within 10 business days) after it becomes actually known to a responsible officer of the trustee. However, except in the case of a default in the payment of the principal of, or interest on, any note, the trustee may withhold such notice if and for so long as it in good faith determines that withholding such notice is in the interests of the noteholders. For the avoidance of doubt, the trustee will not be required to deliver such notice at any time after such default is cured or waived.

Limitation on Suits; Absolute Rights of Noteholders

Except with respect to the rights referred to below, no noteholder may pursue any remedy with respect to the indenture or the notes, unless:

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such noteholder has previously delivered to the trustee notice that an event of default is continuing;
&#x2022;
noteholders of at least 25% in aggregate principal amount of the notes then outstanding deliver a written request to the trustee to pursue such remedy;
&#x2022;
such noteholder(s) offer and, if requested, provide to the trustee security and indemnity satisfactory to the trustee against any loss, liability or expense to the trustee that may result from the trustee&#x2019;s following such request;
&#x2022;
the trustee does not comply with such request within 60 calendar days after its receipt of such request and such offer of security or indemnity; and
&#x2022;
during such 60 calendar day period, noteholders of a majority in aggregate principal amount of the notes then outstanding do not deliver to the trustee a direction that is inconsistent with such request.

However, notwithstanding anything to the contrary, but without limiting the provisions described under the caption &#x201c;&#x2014;Modification and Amendment&#x201d; relating to amendments and supplements without the consent of any noteholder, the right of each holder of a note to receive any payment or delivery, as applicable, of the principal of, or the fundamental change repurchase price or redemption price for, or any interest on, or the consideration due upon conversion of, such note on or after the respective due dates therefor, or to bring suit for the enforcement of any such payment or delivery on or after such respective due dates, will not be impaired or affected without the consent of such holder.

Noteholders of a majority in aggregate principal amount of the notes then outstanding may direct the time, method and place of conducting any proceeding for exercising any remedy available to the trustee or exercising any trust or power conferred on it. However, the trustee may refuse to follow any direction that conflicts with law, the indenture or the notes, or that, subject to the terms of the indenture, the trustee determines may be unduly prejudicial to the rights of other noteholders or may involve the trustee in liability, unless the trustee is offered (and, if requested, provided with) security and indemnity satisfactory to the trustee against any loss, liability or expense to the trustee that may result from the trustee&#x2019;s following such direction.

Default Interest

Payments of any cash amounts due on the notes that are not made when due will accrue interest at a rate per annum equal to the rate per annum at which stated interest accrues on the notes. We refer to such interest, if any, as &#x201c;default interest.&#x201d;

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Special Interest as Sole Remedy for Certain Reporting Defaults

Notwithstanding anything to the contrary described above, we may elect that the sole remedy for any event of default (a &#x201c;reporting event of default&#x201d;) pursuant to paragraph (6) above arising from our failure to comply with our obligations described below under the caption &#x201c;&#x2014;Exchange Act Reports&#x201d; (including our obligations under Section 314(a)(1) of the Trust Indenture Act) will, for each of the first 365 calendar days on which a reporting event of default has occurred and is continuing, consist exclusively of the accrual of special interest on the notes. If we have made such an election, then (i) the notes will be subject to acceleration as described above on account of the relevant reporting event of default from, and including, the 366th calendar day on which a reporting event of default has occurred and is continuing or if we fail to pay any accrued and unpaid special interest when due; and (ii) special interest will cease to accrue on any notes from, and including, such 366th calendar day.

Any special interest that accrues on a note will be payable on the same dates and in the same manner as the stated interest on such note and will accrue at a rate per annum equal to 0.25% of the principal amount thereof for the first 180 days on which special interest accrues and, thereafter, at a rate per annum equal to 0.50% of the principal amount thereof. For the avoidance of doubt, any special interest that accrues on a note will be in addition to the stated interest that accrues on such note.

To make the election to pay special interest as described above, we must provide notice of such election to noteholders before the date on which each reporting event of default first occurs. The notice will also, among other things, briefly describe the periods during which and rate at which special interest will accrue and the circumstances under which the notes will be subject to acceleration on account of such reporting event of default.

Modification and Amendment

For purposes of the notes, the description below under this section titled &#x201c;&#x2014;Modification and Amendment&#x201d; supersedes, in its entirety, the information in the accompanying prospectus under the caption &#x201c;Description of Debt Securities&#x2014;Modification and Waiver.&#x201d;

We and the trustee may, with the consent of holders of a majority in aggregate principal amount of the notes then outstanding, amend or supplement the indenture or the notes or waive compliance with any provision of the indenture or the notes. However, without the consent of each affected noteholder, no amendment or supplement to the indenture or the notes, or waiver of any provision of the indenture or the notes, may:

&#x2022;
reduce the principal, or change the stated maturity, of any note;
&#x2022;
reduce the redemption price or fundamental change repurchase price for any note or change the times at which, or the circumstances under which, the notes may or will be redeemed or repurchased by us;
&#x2022;
reduce the rate, or extend the time for the payment, of interest on any note;
&#x2022;
make any change that adversely affects the conversion rights of any note;
&#x2022;
impair the absolute rights of any holder of a note to receive any payment or delivery, as applicable, of the principal of, or the fundamental change repurchase price or redemption price for, or any interest on, or the consideration due upon conversion of, such note on or after the respective due dates therefor, or to bring suit for the enforcement of any such payment or delivery on or after such due dates;
&#x2022;
change the ranking of the notes;
&#x2022;
make any note payable in money, or at a place of payment, other than that stated in the indenture or the note;
&#x2022;
reduce the amount of notes whose holders must consent to any amendment, supplement, waiver or other modification; or
&#x2022;
make any direct or indirect change to any amendment, supplement, waiver or modification provision of the indenture or the notes that requires the consent of each affected noteholder.

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Notwithstanding anything to the contrary above, we and the trustee may amend or supplement the indenture or the notes without the consent of any noteholder to:

&#x2022;
cure any ambiguity or correct any omission, defect or inconsistency in the indenture or the notes;
&#x2022;
add guarantees with respect to our obligations under the indenture or the notes;
&#x2022;
secure the notes;
&#x2022;
add to our covenants or events of default for the benefit of noteholders or surrender any right or power conferred on us;
&#x2022;
provide for the assumption of our obligations under the indenture and the notes pursuant to, and in compliance with, the provisions described above under the caption &#x201c;&#x2014;Consolidation, Merger and Asset Sale&#x201d;;
&#x2022;
enter into supplemental indentures pursuant to, and in accordance with, the provisions described above under the caption &#x201c;&#x2014;Conversion Rights&#x2014;Effect of Common Stock Change Event&#x201d; in connection with a common stock change event;
&#x2022;
irrevocably elect or eliminate any settlement method or specified dollar amount; provided, however, that no such election or elimination will affect any settlement method theretofore elected (or deemed to be elected) with respect to any note pursuant to the provisions described above under the caption &#x201c;&#x2014;Conversion Rights&#x2014;Settlement Upon Conversion&#x2014;Settlement Method&#x201d;;
&#x2022;
evidence or provide for the acceptance of the appointment of a successor trustee;
&#x2022;
conform the provisions of the indenture and the notes to the &#x201c;Description of Notes&#x201d; section of the preliminary prospectus supplement for this offering, as supplemented by the related pricing term sheet;
&#x2022;
provide for or confirm the issuance of additional notes pursuant to the indenture;
&#x2022;
provide for any transfer restrictions that apply to any notes issued under the indenture (other than the notes issued in this offering, and any notes issued in exchange therefor or in substitution thereof) that, at the time of their original issuance, constitute &#x201c;restricted securities&#x201d; within the meaning of Rule 144 under the Securities Act or that are originally issued in reliance upon Regulation S under the Securities Act;
&#x2022;
comply with any requirement of the SEC in connection with effecting or maintaining the qualification of the indenture, or any related supplemental indenture, under the Trust Indenture Act, as then in effect; or
&#x2022;
make any other change to the indenture or the notes that does not, individually or in the aggregate with all other such changes, adversely affect the rights of noteholders, as such, in any material respect, as determined by us in good faith.

Exchange Act Reports

We will send to the trustee copies of all reports that we are required to file with the SEC pursuant to Section 13(a) or 15(d) of the Exchange Act (other than Form 8-K reports) within 15 calendar days after the date that we are required to so file the same (after giving effect to all applicable grace periods under the Exchange Act). However, we need not send to the trustee any material for which we have received, or are seeking in good faith and have not been denied, confidential treatment by the SEC. Any such report that we file with the SEC through the EDGAR system (or any successor thereto) will be deemed to be sent to the trustee at the time such report is so filed via the EDGAR system (or such successor). Upon the written request of any noteholder, the trustee will provide to the noteholder a copy of any report that we have sent the trustee pursuant to the provisions described above, other than a report that is deemed to be sent to the trustee pursuant to the preceding sentence. We will also comply with our other obligations under Section 314(a)(1) of the Trust Indenture Act.

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The &#x201c;grace periods&#x201d; referred to in the preceding paragraph with respect to any report will include the maximum period afforded by Rule 12b-25 (or any successor rule thereto) under the Exchange Act regardless of whether we file, or indicate in the related Form 12b-25 (or any successor form thereto) that we expect to or will file, such report before the expiration of such maximum period.

Discharge

For purposes of the notes, the description below under this section titled &#x201c;&#x2014;Discharge&#x201d; supersedes, in its entirety, the information in the accompanying prospectus under the caption &#x201c;Description of Debt Securities&#x2014;Defeasance of Debt Securities and Certain Covenants in Certain Circumstances.&#x201d;

Subject to the terms of the indenture, our obligations with respect to the notes under the indenture will be discharged if we deliver all outstanding notes to the trustee for cancellation, or if all outstanding notes have become due and payable (including upon conversion, if the consideration due upon such conversion has been determined) and we have irrevocably deposited with the trustee, or caused to be delivered to noteholders, sufficient cash or other consideration to satisfy all amounts that have become due and payable.

Calculations

Except as otherwise provided in the indenture, we will be responsible for making all calculations called for under the indenture or the notes, including determinations of the last reported sale price, the daily conversion value, the daily cash amount, the daily share amount, the daily VWAP, the trading price, accrued interest on the notes, the redemption price, the fundamental change repurchase price and the conversion rate. We will make all calculations in good faith, and, absent manifest error, our calculations will be final and binding on all noteholders. We will provide a schedule of our calculations to the trustee, and the trustee will promptly forward a copy of each such schedule to any noteholder upon written request.

Trustee

The trustee under the indenture is U.S. Bank Trust Company, National Association. The trustee assumes no responsibility for the accuracy or completeness of the information contained in this prospectus supplement, the accompanying prospectus or the related documents. The trustee and its affiliates may from time to time in the future provide banking and other services to us in the ordinary course of business.

Notices

We will send all notices or communications to noteholders pursuant to the indenture in writing by first class mail, certified or registered, return receipt requested, or by overnight air courier guaranteeing next day delivery, to the noteholders&#x2019; respective addresses shown on the register for the notes. However, in the case of global notes, we are permitted to send notices or communications to noteholders pursuant to the depositary procedures, and notices and communications that we send in this manner will be deemed to have been properly sent to such noteholders in writing.

No Personal Liability of Directors, Officers, Employees and Stockholders

No past, present or future director, officer, employee, incorporator or stockholder of ours, as such, will have any liability for any obligations of ours under the indenture or the notes or for any claim based on, in respect of, or by reason of, such obligations or their creation. By accepting any note, each noteholder will be deemed to waive and release all such liability, and such waiver and release are part of the consideration for the issuance of the notes.

Governing Law; Waiver of Jury Trial

For purposes of the notes, the description below under this section titled &#x201c;&#x2014;Governing Law; Waiver of Jury Trial&#x201d; supersedes, in its entirety, the information in the accompanying prospectus under the caption &#x201c;Description of Debt Securities&#x2014;Governing Law.&#x201d;

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The indenture and the notes, and any claim, controversy or dispute arising under or related to the indenture or the notes, will be governed by and construed in accordance with the laws of the state of New York. The indenture will provide that we and the trustee will irrevocably waive, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to the indenture, the notes or the transactions contemplated by the indenture or the notes.

Submission to Jurisdiction

Any legal suit, action or proceeding arising out of or based upon the indenture or the transactions contemplated by the indenture may be instituted in the federal courts of the United States of America located in the City of New York or the courts of the State of New York, in each case located in the City of New York (collectively, the &#x201c;specified courts&#x201d;), and each party will be deemed to irrevocably submit to the non-exclusive jurisdiction of those courts in any such suit, action or proceeding. Service of any process, summons, notice or document by mail (to the extent allowed under any applicable statute or rule of court) to any party&#x2019;s address as provided in the indenture will be effective service of process for any such suit, action or proceeding brought in any such court. Each of us, the trustee and each noteholder (by its acceptance of any note) will be deemed to irrevocably and unconditionally waive any objection to the laying of venue of any suit, action or other proceeding in the specified courts and to irrevocably and unconditionally waive and agree not to plead or claim any such suit, action or other proceeding has been brought in an inconvenient forum.

Definitions

&#x201c;Affiliate&#x201d; has the meaning set forth in Rule 144 under the Securities Act as in effect on the date we first issue the notes.

&#x201c;Bid solicitation agent&#x201d; means the person who is required to obtain bids for the trading price in accordance with the provisions described under the caption &#x201c;&#x2014;Conversion Rights&#x2014;When the Notes May Be Converted&#x2014;Conversion Upon Satisfaction of Note Trading Price Condition&#x201d; and in the definition of &#x201c;trading price.&#x201d;

&#x201c;Board of directors&#x201d; means our board of directors or a committee of such board duly authorized to act on behalf of such board.

&#x201c;Business day&#x201d; means any day other than a Saturday, a Sunday or any day on which the Federal Reserve Bank of New York is authorized or required by law or executive order to close or be closed.

&#x201c;Capital stock&#x201d; of any person means any and all shares of, interests in, rights to purchase, warrants or options for, participations in, or other equivalents of, in each case however designated, the equity of such person, but excluding any debt securities convertible into, or exchangeable for, such equity.

&#x201c;Cleanup redemption&#x201d; has the meaning set forth above under the caption &#x201c;&#x2014;Optional Redemption&#x2014;Cleanup Redemption.&#x201d;

&#x201c;Close of business&#x201d; means 5:00 p.m., New York City time.

&#x201c;Conversion price&#x201d; means, as of any time, an amount equal to (i) $1,000 divided by (ii) the conversion rate in effect at such time.

&#x201c;Conversion rate&#x201d; initially means shares of our common stock per $1,000 principal amount of notes, which amount is subject to adjustment as described above under the caption &#x201c;&#x2014;Conversion Rights.&#x201d; Whenever in this prospectus supplement we refer to the conversion rate as of a particular date without setting forth a particular time on such date, such reference will be deemed to be to the conversion rate immediately after the close of business on such date.

&#x201c;Daily cash amount&#x201d; means, with respect to any VWAP trading day, the lesser of (i) the applicable daily maximum cash amount; and (ii) the daily conversion value for such VWAP trading day.

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&#x201c;Daily conversion value&#x201d; means, with respect to any VWAP trading day, one-25th of the product of (i) the conversion rate on such VWAP trading day; and (ii) the daily VWAP per share of our common stock on such VWAP trading day.

&#x201c;Daily maximum cash amount&#x201d; means, with respect to the conversion of any note, the quotient obtained by dividing (i) the specified dollar amount applicable to such conversion by (ii) 25.

&#x201c;Daily share amount&#x201d; means, with respect to any VWAP trading day, the quotient obtained by dividing (i) the excess, if any, of the daily conversion value for such VWAP trading day over the applicable daily maximum cash amount by (ii) the daily VWAP for such VWAP trading day. For the avoidance of doubt, the daily share amount will be zero for such VWAP trading day if such daily conversion value does not exceed such daily maximum cash amount.

&#x201c;Daily VWAP&#x201d; means, for any VWAP trading day, the per share volume-weighted average price of our common stock as displayed under the heading &#x201c;Bloomberg VWAP&#x201d; on Bloomberg page &#x201c;VKTX AQR&#x201d; (or, if such page is not available, its equivalent successor page) in respect of the period from the scheduled open of trading until the scheduled close of trading of the primary trading session on such VWAP trading day (or, if such volume-weighted average price is unavailable, the market value of one share of our common stock on such VWAP trading day, determined, using a volume-weighted average price method, by a nationally recognized independent investment banking firm we select, which may be any of the underwriters). The daily VWAP will be determined without regard to after-hours trading or any other trading outside of the regular trading session.

&#x201c;Default&#x201d; means any event that is (or, after notice, passage of time or both, would be) an event of default.

&#x201c;Default interest&#x201d; has the meaning set forth above under the caption &#x201c;&#x2014;Events of Default&#x2014;Default Interest.&#x201d;

&#x201c;Depositary procedures&#x201d; means, with respect to any conversion, transfer, exchange or other transaction involving a global note or any beneficial interest therein, the rules and procedures of the depositary applicable to such conversion, transfer, exchange or transaction.

&#x201c;DTC&#x201d; means The Depository Trust Company.

&#x201c;Ex-dividend date&#x201d; means, with respect to an issuance, dividend or distribution on our common stock, the first date on which shares of our common stock trade on the applicable exchange or in the applicable market, regular way, without the right to receive such issuance, dividend or distribution (including pursuant to due bills or similar arrangements required by the relevant stock exchange). For the avoidance of doubt, any alternative trading convention on the applicable exchange or market in respect of our common stock under a separate ticker symbol or CUSIP number will not be considered &#x201c;regular way&#x201d; for this purpose.

&#x201c;Exchange Act&#x201d; means the U.S. Securities Exchange Act of 1934, as amended.

&#x201c;Fundamental change&#x201d; means any of the following events:

(i)
a &#x201c;person&#x201d; or &#x201c;group&#x201d; (within the meaning of Section 13(d)(3) of the Exchange Act), other than us or our &#x201c;wholly owned subsidiaries&#x201d; (as defined below), or any employee benefit plans of ours or our wholly owned subsidiaries, files any report with the SEC that discloses that such person or group has become the direct or indirect &#x201c;beneficial owner&#x201d; (as defined below) of shares of our common stock representing more than 50% of the voting power of all of our common stock; provided, however, that no &#x201c;person&#x201d; or &#x201c;group&#x201d; will be deemed to be the beneficial owner of any securities tendered pursuant to a tender or exchange offer made by or on behalf of such &#x201c;person&#x201d; or &#x201c;group&#x201d; until such tendered securities are accepted for purchase or exchange under such offer;
(ii)
the consummation of: (1) any sale, lease or other transfer, in one transaction or a series of transactions, of all or substantially all of the assets of us and our subsidiaries, taken as a whole, to any person, other than solely to one or more of our wholly owned subsidiaries; or (2) any transaction or series of related transactions in connection with which (whether by means of merger, consolidation, share exchange, combination, reclassification, recapitalization, acquisition, liquidation or otherwise) all of our common stock is exchanged for, converted into, acquired for, or constitutes solely the right to receive, other securities, cash or other property (other than changes resulting solely from a stock split or a stock combination, or a change in par value, of our common stock); provided,

S-58

however, that any merger, consolidation, share exchange or combination of us pursuant to which the persons that directly or indirectly &#x201c;beneficially owned&#x201d; (as defined below) all classes of our common equity immediately before such transaction directly or indirectly &#x201c;beneficially own,&#x201d; immediately after such transaction, more than 50% of all classes of common equity of the surviving, continuing or acquiring company or other transferee, as applicable, or the parent thereof, in substantially the same proportions vis-&agrave;-vis each other as immediately before such transaction will be deemed not to be a fundamental change pursuant to this clause (ii);
(iii)
our stockholders approve any plan or proposal for our liquidation or dissolution; or
(iv)
our common stock ceases to be listed on any of the New York Stock Exchange, the NYSE American, the Nasdaq Capital Market, the Nasdaq Global Market or the Nasdaq Global Select Market (or any of their respective successors);

provided, however, that a transaction or event described in clause (i) or (ii) above will not constitute a fundamental change if at least 90% of the consideration received or to be received by the holders of our common stock (excluding cash payments for fractional shares or pursuant to dissenters rights), in connection with such transaction or event, consists of shares of common stock or other corporate common equity interests listed (or depositary receipts representing shares of common stock or other corporate common equity interests, which depositary receipts are listed) on any of the New York Stock Exchange, the NYSE American, the Nasdaq Capital Market, the Nasdaq Global Market or the Nasdaq Global Select Market (or any of their respective successors), or that will be so listed when issued or exchanged in connection with such transaction or event, and such transaction or event constitutes a common stock change event whose reference property consists of such consideration.

For the avoidance of doubt, references in this definition to us, and to our &#x201c;common stock&#x201d; and &#x201c;common equity,&#x201d; will be subject to (i) the provisions described above under the caption &#x201c;&#x2014;Consolidation, Merger and Asset Sale&#x201d;; and (ii) the provision described above in clause (iii) of the fifth bullet point under the caption &#x201c;&#x2014;Conversion Rights&#x2014;Effect of Common Stock Change Event.&#x201d;

For the purposes of this definition, (x) any transaction or event described in both clause (i) and in clause (ii)(1) or (2) above (without regard to the proviso in clause (ii)) will be deemed to occur solely pursuant to clause (ii) above (subject to such proviso); and (y) whether a person is a &#x201c;beneficial owner,&#x201d; whether shares are &#x201c;beneficially owned,&#x201d; and percentage beneficial ownership, will be determined in accordance with Rule 13d-3 under the Exchange Act subject to the proviso to clause (i) above.

&#x201c;Holder&#x201d; and &#x201c;noteholder&#x201d; mean a person in whose name a note is registered in the register for the notes.

&#x201c;Last reported sale price&#x201d; of our common stock for any trading day means the closing sale price per share (or, if no closing sale price is reported, the average of the last bid price and the last ask price per share or, if more than one in either case, the average of the average last bid prices and the average last ask prices per share) of our common stock on such trading day as reported in composite transactions for the principal U.S. national or regional securities exchange on which our common stock is then listed. If our common stock is not listed on a U.S. national or regional securities exchange on such trading day, then the last reported sale price will be the last quoted bid price per share of our common stock on such trading day in the over-the-counter market as reported by OTC Markets Group Inc. or a similar organization. If our common stock is not so quoted on such trading day, then the last reported sale price will be the average of the mid-point of the last bid price and the last ask price per share of our common stock on such trading day from a nationally recognized independent investment banking firm we select, which may be any of the underwriters.

&#x201c;Make-whole fundamental change&#x201d; means (i) a fundamental change (determined after giving effect to the proviso immediately after clause (iv) of the definition thereof, but without regard to the proviso to clause (ii)(2) of such definition); or (ii) the sending of any redemption notice with respect to a provisional redemption or a cleanup redemption pursuant to the provisions described above under the caption &#x201c;&#x2014;Optional Redemption&#x201d;; provided, however, that the sending of any such redemption notice for a provisional redemption will constitute a make-whole fundamental change only with respect to the notes called for redemption pursuant to such notice and not with respect to any other notes.

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&#x201c;Make-whole fundamental change conversion period&#x201d; has the following meaning:

(i)
in the case of a make-whole fundamental change pursuant to clause (i) of the definition thereof, the period from, and including, the make-whole fundamental change effective date of such make-whole fundamental change to, and including, the 35th trading day after such make-whole fundamental change effective date (or, if such make-whole fundamental change also constitutes a fundamental change (other than an exempted fundamental change), to, but excluding, the related fundamental change repurchase date); and
(ii)
in the case of a make-whole fundamental change pursuant to clause (ii) of the definition thereof, the period from, and including, the date we send the redemption notice for the related redemption to, and including, the second business day immediately before the related redemption date;

provided, however, that if the conversion date for the conversion of a note that has been called for redemption occurs during the make-whole fundamental change conversion period for both a make-whole fundamental change occurring pursuant to clause (i) of the definition of &#x201c;make-whole fundamental change&#x201d; and a make-whole fundamental change resulting from such redemption pursuant to clause (ii) of such definition, then, solely for purposes of such conversion, (x) such conversion date will be deemed to occur solely during the make-whole fundamental change conversion period for the make-whole fundamental change with the earlier make-whole fundamental change effective date; and (y) the make-whole fundamental change with the later make-whole fundamental change effective date will be deemed not to have occurred.

&#x201c;Make-whole fundamental change effective date&#x201d; means (i) with respect to a make-whole fundamental change pursuant to clause (i) of the definition thereof, the date on which such make-whole fundamental change occurs or becomes effective; and (ii) with respect to a make-whole fundamental change pursuant to clause (ii) of the definition thereof, the applicable &#x201c;redemption notice date&#x201d; (as defined below).

&#x201c;Market disruption event&#x201d; means, with respect to any date, the occurrence or existence, during the one-half hour period ending at the scheduled close of trading on such date on the principal U.S. national or regional securities exchange or other market on which our common stock is listed for trading or trades, of any material suspension or limitation imposed on trading (by reason of movements in price exceeding limits permitted by the relevant exchange or otherwise) in our common stock or in any options contracts or futures contracts relating to our common stock.

&#x201c;Maturity date&#x201d; means October 15, 2032.

&#x201c;Observation period&#x201d; means, with respect to any note to be converted, (i) subject to clause (ii) below, if the conversion date for such note occurs before July 15, 2032, the 25 consecutive VWAP trading days beginning on, and including, the second VWAP trading day immediately after such conversion date; (ii) if such conversion date occurs on or after the date we have sent a redemption notice calling all or any notes for redemption and on or before the second business day before the related redemption date, the 25 consecutive VWAP trading days beginning on, and including, the 26th scheduled trading day immediately before such redemption date; and (iii) subject to clause (ii) above, if such conversion date occurs on or after July 15, 2032, the 25 consecutive VWAP trading days beginning on, and including, the 26th scheduled trading day immediately before the maturity date.

&#x201c;Open of business&#x201d; means 9:00 a.m., New York City time.

&#x201c;Person&#x201d; means any individual, corporation, partnership, limited liability company, joint venture, association, joint-stock company, trust, unincorporated organization or government or other agency or political subdivision thereof. Any division or series of a limited liability company, limited partnership or trust will constitute a separate &#x201c;person.&#x201d;

&#x201c;Provisional redemption&#x201d; has the meaning set forth above under the caption &#x201c;&#x2014;Optional Redemption&#x2014;Provisional Redemption.&#x201d;

&#x201c;Qualified successor entity&#x201d; means, with respect to a business combination event, a corporation; provided, however, that a limited liability company, limited partnership or other similar entity will also constitute a qualified successor entity with respect to such business combination event if either (i) such business combination event is an exempted fundamental change; or (ii) both of the following conditions are satisfied: (1) either (a) such limited liability company,

S-60

limited partnership or other similar entity, as applicable, is treated as a corporation or is a direct or indirect, wholly owned subsidiary of, and disregarded as an entity separate from, a corporation, in each case for U.S. federal income tax purposes; or (b) we have received an opinion of a nationally recognized tax counsel to the effect that such business combination event will not be treated as an exchange under Section 1001 of the Internal Revenue Code of 1986, as amended, for holders or beneficial owners of the notes; and (2) either (a) such business combination event constitutes a common stock change event whose reference property consists solely of any combination of cash in U.S. dollars and shares of common stock or other corporate common equity interests of an entity that is (I) treated as a corporation for U.S. federal income tax purposes; (II) duly organized and existing under the laws of the United States of America, any State thereof or the District of Columbia; and (III) the direct or indirect parent of such limited liability company, limited partnership or other similar entity; or (b) both of the following conditions are satisfied: (I) such business combination event does not constitute a common stock change event; and (II) we (x) remain an obligor of the notes following such business combination event; and (y) are the direct or indirect parent of such limited liability company, limited partnership or other similar entity.

&#x201c;Redemption&#x201d; means a provisional redemption or a cleanup redemption.

&#x201c;Redemption notice date&#x201d; means, with respect to a redemption, the date on which we send the related redemption notice pursuant to the provisions described above under the caption &#x201c;&#x2014;Optional Redemption&#x2014;Redemption Notice.&#x201d;

&#x201c;Scheduled trading day&#x201d; means any day that is scheduled to be a trading day on the principal U.S. national or regional securities exchange on which our common stock is then listed or, if our common stock is not then listed on a U.S. national or regional securities exchange, on the principal other market on which our common stock is then traded. If our common stock is not so listed or traded, then &#x201c;scheduled trading day&#x201d; means a business day.

&#x201c;Securities Act&#x201d; means the U.S. Securities Act of 1933, as amended.

&#x201c;Significant subsidiary&#x201d; of any person means any subsidiary of that person that constitutes a &#x201c;significant subsidiary&#x201d; (as defined in Rule 1-02(w) of Regulation S-X under the Exchange Act) of that person; provided, however, that, if a subsidiary meets the criteria of clause (1)(iii) of the definition of &#x201c;significant subsidiary&#x201d; in Rule 1-02(w) but not clause (1)(i) or (1)(ii) thereof (or, if applicable, the respective successor clauses to the aforementioned clauses), then such subsidiary will be deemed not to be a significant subsidiary of that person unless such subsidiary&#x2019;s income from continuing operations before income taxes, exclusive of amounts attributable to any non-controlling interests, for the last completed fiscal year before the date of determination exceeds $20,000,000.

&#x201c;Specified dollar amount&#x201d; means, with respect to the conversion of a note to which combination settlement applies, the maximum cash amount per $1,000 principal amount of such note deliverable upon such conversion (excluding cash in lieu of any fractional share of common stock).

&#x201c;Stated interest&#x201d; has the meaning set forth above under the caption &#x201c;&#x2014;Interest.&#x201d;

&#x201c;Stock price&#x201d; has the following meaning for any make-whole fundamental change: (i) if the holders of our common stock receive only cash in consideration for their shares of our common stock in such make-whole fundamental change and such make-whole fundamental change is pursuant to clause (ii) of the definition of &#x201c;fundamental change,&#x201d; then the stock price is the amount of cash paid per share of our common stock in such make-whole fundamental change; and (ii) in all other cases, the stock price is the average of the last reported sale prices per share of our common stock for the five consecutive trading days ending on, and including, the trading day immediately before the make-whole fundamental change effective date of such make-whole fundamental change.

&#x201c;Subsidiary&#x201d; means, with respect to any person, (i) any corporation, association or other business entity (other than a partnership or limited liability company) of which more than 50% of the total voting power of the capital stock entitled (without regard to the occurrence of any contingency, but after giving effect to any voting agreement or stockholders&#x2019; agreement that effectively transfers voting power) to vote in the election of directors, managers or trustees, as applicable, of such corporation, association or other business entity is owned or controlled, directly or indirectly, by such person or one or more of the other subsidiaries of such person; and (ii) any partnership or limited liability company where (x) more than 50% of the capital accounts, distribution rights, equity and voting interests, or of the general and limited partnership interests, as applicable, of such partnership or limited liability company are owned or

S-61

controlled, directly or indirectly, by such person or one or more of the other subsidiaries of such person, whether in the form of membership, general, special or limited partnership or limited liability company interests or otherwise; and (y) such person or any one or more of the other subsidiaries of such person is a controlling general partner of, or otherwise controls, such partnership or limited liability company.

&#x201c;Trading day&#x201d; means any day on which (i) trading in our common stock generally occurs on the principal U.S. national or regional securities exchange on which our common stock is then listed or, if our common stock is not then listed on a U.S. national or regional securities exchange, on the principal other market on which our common stock is then traded; and (ii) there is no &#x201c;market disruption event&#x201d; (as defined above in this &#x201c;&#x2014;Definitions&#x201d; section). If our common stock is not so listed or traded, then &#x201c;trading day&#x201d; means a business day.

&#x201c;Trading price&#x201d; of the notes on any trading day means the average of the secondary market bid quotations, expressed as a cash amount per $1,000 principal amount of notes, obtained by the bid solicitation agent for $1,000,000 (or such lesser amount as may then be outstanding) in principal amount of notes at approximately 3:30 p.m., New York City time, on such trading day from three nationally recognized independent securities dealers we select, which may include any of the underwriters; provided, however, that, if three such bids cannot reasonably be obtained by the bid solicitation agent but two such bids are obtained, then the average of the two bids will be used, and if only one such bid can reasonably be obtained by the bid solicitation agent, then that one bid will be used. If, on any trading day, (i) the bid solicitation agent cannot reasonably obtain at least one bid for $1,000,000 (or such lesser amount as may then be outstanding) in principal amount of notes from a nationally recognized independent securities dealer; (ii) we are not acting as the bid solicitation agent and we fail to instruct the bid solicitation agent to obtain bids when required; or (iii) the bid solicitation agent fails to solicit bids when required, then, in each case, the trading price per $1,000 principal amount of notes on such trading day will be deemed to be less than 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day.

&#x201c;VWAP market disruption event&#x201d; means, with respect to any date, (i) the failure by the principal U.S. national or regional securities exchange on which our common stock is then listed, or, if our common stock is not then listed on a U.S. national or regional securities exchange, the principal other market on which our common stock is then traded, to open for trading during its regular trading session on such date; or (ii) the occurrence or existence, for more than one half hour period in the aggregate, of any suspension or limitation imposed on trading (by reason of movements in price exceeding limits permitted by the relevant exchange or otherwise) in our common stock or in any options contracts or futures contracts relating to our common stock, and such suspension or limitation occurs or exists at any time before 1:00 p.m., New York City time, on such date.

&#x201c;VWAP trading day&#x201d; means a day on which (i) there is no VWAP market disruption event; and (ii) trading in our common stock generally occurs on the principal U.S. national or regional securities exchange on which our common stock is then listed or, if our common stock is not then listed on a U.S. national or regional securities exchange, on the principal other market on which our common stock is then traded. If our common stock is not so listed or traded, then &#x201c;VWAP trading day&#x201d; means a business day.

&#x201c;Wholly owned subsidiary&#x201d; of a person means any subsidiary of such person all of the outstanding capital stock or other ownership interests of which (other than directors&#x2019; qualifying shares) are owned by such person or one or more wholly owned subsidiaries of such person.

Book Entry, Settlement and Clearance

For purposes of the notes, the description below under this section titled &#x201c;&#x2014;Book Entry, Settlement and Clearance&#x201d; supersedes, in its entirety, the information in the accompanying prospectus under the caption &#x201c;Legal Ownership of Securities.&#x201d;

Global Notes

The notes will be initially issued in the form of one or more notes registered in the name of Cede & Co., as nominee of DTC, without interest coupons (the &#x201c;global notes&#x201d;), and will be deposited with the trustee as custodian for DTC.

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Only persons who have accounts with DTC (&#x201c;DTC participants&#x201d;) or persons who hold interests through DTC participants may own beneficial interests in a global note. We expect that, under procedures established by DTC:

&#x2022;
upon deposit of a global note with DTC&#x2019;s custodian, DTC will credit portions of the principal amount of the global note to the accounts of the DTC participants designated by the underwriters; and
&#x2022;
ownership of beneficial interests in a global note will be shown on, and transfers of such interests will be effected only through, records maintained by DTC (with respect to interests of DTC participants) and the records of DTC participants (with respect to other owners of beneficial interests in the global note).

Book-Entry Procedures for Global Notes

All interests in a global note will be subject to the operations and procedures of DTC. Accordingly, you must allow for sufficient time in order to comply with those operations and procedures if you wish to exercise any of your rights with respect to global notes. The operations and procedures of DTC are controlled by DTC and may be changed at any time. None of us, the trustee or any of the underwriters will be responsible for those operations or procedures.

DTC has advised us that it is:

&#x2022;
a limited purpose trust company organized under the laws of the State of New York;
&#x2022;
a &#x201c;banking organization&#x201d; within the meaning of the New York State Banking Law;
&#x2022;
a member of the Federal Reserve System;
&#x2022;
a &#x201c;clearing corporation&#x201d; within the meaning of the Uniform Commercial Code; and
&#x2022;
a &#x201c;clearing agency&#x201d; registered under Section 17A of the Exchange Act.

DTC was created to hold securities for its participants and to facilitate the clearance and settlement of securities transactions between its participants through electronic book-entry changes to the accounts of its participants. DTC&#x2019;s participants include securities brokers and dealers (including the underwriters), banks and trust companies, clearing corporations and other organizations. Indirect access to DTC&#x2019;s book-entry system is also available to other &#x201c;indirect participants,&#x201d; such as banks, brokers, dealers and trust companies, who directly or indirectly clear through or maintain a custodial relationship with a DTC participant. Purchasers of notes who are not DTC participants may beneficially own securities held by or on behalf of DTC only through DTC participants or indirect participants in DTC.

So long as DTC or its nominee is the registered owner of a global note, DTC or that nominee will be considered the sole owner or holder of the notes represented by that global note for all purposes under the indenture. Except as provided below, owners of beneficial interests in a global note:

&#x2022;
will not be entitled to have notes represented by the global note registered in their names;
&#x2022;
will not receive or be entitled to receive physical, certificated notes; and
&#x2022;
will not be considered the owners or holders of the notes under the indenture for any purpose.

As a result, each investor who owns a beneficial interest in a global note must rely on the procedures of DTC (and, if the investor is not a participant or an indirect participant in DTC, on the procedures of the DTC participant through whom the investor owns its interest) to exercise any rights of a noteholder under the indenture.

Payments on any global notes will be made to DTC&#x2019;s nominee as the registered holder of the global note. None of us, the trustee or any of the underwriters will have any responsibility or liability for the payment of amounts to owners of beneficial interests in a global note, for any aspect of the records relating to, or payments made on account of, those interests by DTC or for maintaining, supervising or reviewing any records of DTC relating to those interests. Payments by participants and indirect participants in DTC to the owners of beneficial interests in a global note will be governed

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by standing instructions and customary industry practice and will be the responsibility of those participants or indirect participants and DTC.

Transfers between participants in DTC will be effected under DTC&#x2019;s procedures and will be settled in same-day funds.

Physical Notes

A global note will be exchanged, pursuant to customary procedures, for one or more physical notes only if:

&#x2022;
DTC notifies us or the trustee that it is unwilling or unable to continue as depositary for such global note or DTC ceases to be a &#x201c;clearing agency&#x201d; registered under Section 17A of the Exchange Act and, in each case, we fail to appoint a successor depositary within 90 days of such notice or cessation;
&#x2022;
an event of default has occurred and is continuing and we, the trustee or the registrar has received a written request from DTC, or from a holder of a beneficial interest in such global note, to exchange such global note or beneficial interest, as applicable, for one or more physical notes; or
&#x2022;
we, in our sole discretion, permit the exchange of any beneficial interest in such global note for one or more physical notes at the request of the owner of such beneficial interest.

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Material U.S. Federal Income Tax Considerations

The following is a summary of material U.S. federal income tax considerations of the purchase, ownership, conversion and disposition of the notes issued pursuant to this offering and the ownership and disposition of the shares of our common stock into which the notes may be converted, but does not purport to be a complete analysis of all potential tax effects. The effects of other U.S. federal tax laws, such as estate and gift tax laws, and any applicable state, local or non-U.S. tax laws are not discussed. This summary is based upon provisions of the U.S. Internal Revenue Code of 1986, as amended (the &#x201c;Code&#x201d;), applicable Treasury regulations promulgated thereunder, judicial decisions, and published rulings and administrative pronouncements of the Internal Revenue Service (the &#x201c;IRS&#x201d;), in each case in effect as of the date hereof. These authorities may change or be subject to differing interpretations. Any such change or differing interpretation may be applied retroactively in a manner that could adversely affect a holder of the notes or the shares of our common stock into which the notes may be converted. We have not sought and will not seek any rulings from the IRS regarding the matters discussed below. There can be no assurance the IRS or a court will not take a contrary position to that discussed below regarding the tax consequences of the purchase, ownership, conversion and disposition of the notes and the ownership and disposition of the shares of our common stock into which the notes may be converted.

Except where noted, this summary addresses only notes or shares of common stock held as &#x201c;capital assets&#x201d; within the meaning of Section 1221 of the Code (generally, property held for investment) by a beneficial owner who purchased the notes on original issuance for cash at their &#x201c;issue price&#x201d; within the meaning of Section 1273 of the Code (i.e., the first price at which a substantial amount of the notes is sold for cash to persons other than bond houses, brokers, or similar persons or organizations acting in the capacity of underwriters, placement agents or wholesalers). This summary does not address all aspects of U.S. federal income taxes relevant to holders of notes or common stock (including the potential application of the Medicare contribution tax), nor does it address all tax consequences that may be relevant to such holders in light of their personal circumstances or particular situations, such as:

&#x2022;
tax consequences to holders who may be subject to special tax treatment, including dealers in securities or currencies, banks, financial institutions, regulated investment companies, real estate investment trusts, tax-exempt organizations, governmental organizations, &#x201c;controlled foreign corporations,&#x201d; &#x201c;foreign controlled foreign corporations,&#x201d; &#x201c;passive foreign investment companies,&#x201d; insurance companies or traders in securities that elect to use a mark-to-market method of tax accounting for their securities;
&#x2022;
tax consequences to persons holding notes or common stock as a part of a hedging, integrated or conversion transaction or a straddle, or persons deemed to sell notes or common stock under the constructive sale provisions of the Code;
&#x2022;
tax consequences to U.S. holders (as defined below) whose &#x201c;functional currency&#x201d; is not the U.S. dollar;
&#x2022;
tax consequences to partnerships or other pass-through entities or arrangements, or investors that hold the notes or our common stock through partnerships or other pass-through entities or arrangements;
&#x2022;
tax consequences to persons subject to special tax accounting rules as a result of any item of gross income with respect to the notes or common stock being taken into account in an applicable financial statement; and
&#x2022;
any minimum tax consequences.

If an entity or arrangement treated as a partnership for U.S. federal income tax purposes holds notes or common stock, the tax treatment of a partner in the partnership will depend on the status of the partner, the activities of the partnership and certain determinations made at the partner level. Accordingly, partnerships holding notes or common stock and the partners in such partnerships should consult their tax advisors.

THIS DISCUSSION IS FOR INFORMATIONAL PURPOSES ONLY AND IS NOT TAX ADVICE. YOU SHOULD CONSULT YOUR TAX ADVISOR WITH RESPECT TO THE APPLICATION OF THE U.S. FEDERAL INCOME TAX LAWS TO YOUR PARTICULAR SITUATION AS WELL AS ANY TAX

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CONSEQUENCES OF THE PURCHASE, OWNERSHIP, CONVERSION AND DISPOSITION OF NOTES AND THE OWNERSHIP AND DISPOSITION OF THE COMMON STOCK ARISING UNDER OTHER U.S. FEDERAL TAX LAWS (INCLUDING ESTATE AND GIFT TAX LAWS), UNDER THE LAWS OF ANY STATE, LOCAL OR NON-U.S. TAXING JURISDICTION OR UNDER ANY APPLICABLE TAX TREATY.

As used herein, a &#x201c;U.S. holder&#x201d; is a beneficial owner of a note or common stock received upon conversion of a note that is, for U.S. federal income tax purposes:

&#x2022;
an individual who is a citizen or resident of the United States;
&#x2022;
a corporation (or any other entity treated as a corporation for U.S. federal income tax purposes) created or organized in or under the laws of the United States, any state thereof or the District of Columbia;
&#x2022;
an estate the income of which is subject to U.S. federal income taxation regardless of its source; or
&#x2022;
a trust, if it (i) is subject to the primary supervision of a court within the United States and one or more U.S. persons have the authority to control all substantial decisions of the trust, or (ii) has a valid election in effect under applicable Treasury regulations to be treated as a United States person.

A &#x201c;non-U.S. holder&#x201d; is a beneficial owner of a note or common stock received upon conversion of a note that is an individual, corporation (or any other entity treated as a corporation for U.S. federal income tax purposes), estate or trust that is not a U.S. holder. Special rules may apply to certain non-U.S. holders such as corporations that accumulate earnings to avoid U.S. federal income tax or, in certain circumstances, individuals who are U.S. expatriates. Consequently, non-U.S. holders should consult their tax advisors to determine the U.S. federal, state and local, and non-U.S. and other tax consequences that may be relevant to them in light of their particular circumstances.

Consequences to U.S. Holders

Interest on the Notes

It is anticipated, and this discussion assumes, that the notes will be issued with less than de minimis original issue discount for U.S. federal income tax purposes. In such case, stated interest on a note generally will be taxable to a U.S. holder as ordinary income at the time it is received or accrues in accordance with the U.S. holder&#x2019;s usual method of accounting for U.S. federal income tax purposes.

Additional Payments

In certain circumstances, we may be obligated to make payments on the notes in excess of stated principal and interest or to make payments in advance of their scheduled times. We intend to take the position that these contingencies should not cause the notes to be treated as contingent payment debt instruments under the applicable Treasury regulations. Assuming such position is respected by the IRS, a U.S. holder may be required to include in income the amount of any such additional payments at the time such payments are received or accrued in accordance with such U.S. holder&#x2019;s method of accounting for U.S. federal income tax purposes. Our position is binding on a U.S. holder, unless the holder discloses in the proper manner to the IRS that it is taking a different position. If the IRS successfully challenged our position, and the notes were treated as contingent payment debt instruments, a U.S. holder would be required to accrue interest income based upon a &#x201c;comparable yield,&#x201d; regardless of the U.S. holder&#x2019;s method of accounting, which yield would generally be at a rate higher than the notes&#x2019; stated interest rate. And the U.S. holder would be required to treat as ordinary income, rather than capital gain, any gain recognized on a sale, exchange, retirement or redemption of a note (including all gain realized upon conversion, even if the U.S. holder receives shares of our common stock).. This discussion assumes that the notes will not be considered contingent payment debt instruments and that no such other payments will be due. U.S. holders are urged to consult their tax advisors regarding the potential application to the notes of the contingent payment debt instrument rules and the consequences thereof.

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Sale, Exchange, Redemption or Other Taxable Disposition of Notes

Except as provided below under &#x201c;&#x2014;Conversion of Notes,&#x201d; a U.S. holder generally will recognize gain or loss upon the sale, exchange, redemption or other taxable disposition of a note (including an exchange with a designated financial institution in lieu of conversion, as described in &#x201c;Description of Notes&#x2014;Conversion Rights&#x2014;Exchange in Lieu of Conversion&#x201d;) equal to the difference between the amount realized and such U.S. holder&#x2019;s adjusted tax basis in the note. The amount realized by a U.S. holder will include the amount of any cash and the fair market value of any other property received for the note, but does not include any amount attributable to accrued but unpaid interest. Amounts attributable to accrued but unpaid interest are treated as interest as described above under &#x201c;&#x2014;Interest on the Notes.&#x201d; A U.S. holder&#x2019;s adjusted tax basis in a note generally will be equal to the amount that the U.S. holder paid for the note, increased by the amount, if any, included in income as a dividend by the U.S. holder upon an adjustment (or failure to make an adjustment) to the conversion rate of the note, as described in &#x201c;&#x2014;Constructive Distributions&#x201d; below.

Any gain or loss recognized on a taxable disposition of a note generally will be capital gain or loss. If, at the time of the sale, exchange, redemption or other taxable disposition of a note, a U.S. holder held the note for more than one year, such gain or loss generally will be long-term capital gain or loss. Otherwise, such gain or loss will be short-term capital gain or loss. In the case of certain non-corporate U.S. holders (including individuals), long-term capital gains are generally eligible for a reduced rate of U.S. federal income tax. The deductibility of capital losses is subject to limitations.

Conversion of Notes

If a U.S. holder presents a note for conversion, the U.S. holder may receive solely cash, solely common stock, or a combination of cash and common stock in exchange for the note, depending upon our chosen settlement method.

If a U.S. holder receives solely cash in exchange for a note upon conversion, the U.S. holder will generally recognize gain or loss upon such conversion, and the U.S. holder&#x2019;s gain or loss will be determined in the same manner as if the U.S. holder disposed of the notes in a taxable disposition (as described above under &#x201c;&#x2014;Sale, Exchange, Redemption or Other Taxable Disposition of Notes&#x201d;).

If a U.S. holder receives solely common stock in exchange for notes upon conversion (excluding an exchange with a designated financial institution in lieu of conversion, as described in &#x201c;Description of Notes&#x2014;Conversion Rights&#x2014;Exchange in Lieu of Conversion,&#x201d; which would be taxable as described above, under &#x201c;&#x2014;Sale, Exchange, Redemption or Other Taxable Disposition of Notes,&#x201d; and in which case the holder would have a tax basis in the shares of common stock equal to their fair market value at the time of the conversion, and a holding period beginning the day after the date of receipt), the U.S. holder generally will not recognize gain or loss upon the conversion of the notes into common stock except to the extent of (i) cash received in lieu of a fractional share and (ii) amounts received with respect to accrued but unpaid interest (which will be treated as described above under &#x201c;&#x2014;Interest on the Notes&#x201d;).

The amount of gain or loss a U.S. holder will recognize on the receipt of cash in lieu of a fractional share will be equal to the difference between the amount of cash the U.S. holder receives in respect of the fractional share and the portion of the U.S. holder&#x2019;s adjusted tax basis in the note that is allocable to the fractional share. Any such gain or loss generally will be capital gain or loss and generally will be long-term capital gain or loss, if at the time of the conversion, the note has been held for more than one year. The tax basis of shares of common stock received upon a conversion (other than shares attributable to accrued but unpaid interest, the tax basis of which will equal their fair market value) will equal the adjusted tax basis of the note that was converted (excluding the portion of the adjusted tax basis that is allocable to any fractional share). The U.S. holder&#x2019;s holding period for the shares of common stock will include the period during which the U.S. holder held the notes, except that the holding period for any shares received with respect to accrued but unpaid interest will commence on the day after the date of receipt.

As described below, the tax treatment of a conversion of a note into cash and common stock is uncertain and subject to different possible characterizations, either as a recapitalization or, as an alternative treatment, as part conversion and part redemption, and U.S. holders should consult their tax advisors regarding the consequences of such a conversion.

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Treatment as a Recapitalization. If a combination of cash and common stock is received by a U.S. holder upon conversion of a note (excluding an exchange with a designated financial institution in lieu of conversion, as described in &#x201c;Description of Notes&#x2014;Conversion Rights&#x2014;Exchange in Lieu of Conversion,&#x201d; which would be taxable as described above, under &#x201c;&#x2014;Sale, Exchange, Redemption or Other Taxable Disposition of Notes&#x201d;), we intend to take the position that the notes are securities for relevant U.S. federal income tax purposes and to treat the conversion as a recapitalization. However, this position is not free from doubt and there can be no assurance in this regard. In such case, gain, but not loss, would be recognized by the U.S. holder equal to the excess of the fair market value of our common stock (including any fractional share deemed received) and cash received (other than amounts attributable to accrued but unpaid interest, which will be treated as described above under &#x201c;&#x2014;Interest on the Notes,&#x201d; and other than any cash received in lieu of a fractional share) over the U.S. holder&#x2019;s adjusted tax basis in the note, but in no event would the gain recognized exceed the amount of cash received (excluding any cash received in lieu of a fractional share or attributable to accrued but unpaid interest). Cash received in lieu of a fractional share of our common stock upon a conversion of a note should be treated as a payment in exchange for the fractional share of our common stock. Accordingly, the receipt of cash in lieu of a fractional share of our common stock should generally result in capital gain or loss, which would be equal to the difference between the amount of cash received in lieu of a fractional share and the portion of the U.S. holder&#x2019;s tax basis in our common stock received that is allocable to the fractional share. Any gain or loss recognized by a U.S. holder on conversion of a note generally would be capital gain or loss and generally would be long-term capital gain or loss if, at the time of the conversion, the note has been held for more than one year.

The tax basis of our common stock received upon such a conversion (including any fractional share deemed to be received by the U.S. holder, but excluding any common stock attributable to accrued but unpaid interest, the tax basis of which would equal its fair market value) would equal the adjusted tax basis of the note that was converted, reduced by the amount of any cash received (excluding cash received in lieu of a fractional share or attributable to accrued but unpaid interest), and increased by the amount of gain, if any, recognized (other than gain recognized on any cash received with respect to a fractional share). A U.S. holder&#x2019;s holding period for common stock would include the period during which the U.S. holder held the note, except that the holding period for any common stock received with respect to accrued but unpaid interest would commence on the day after our common stock is received.

Alternative Treatment as Part Conversion and Part Redemption. If the conversion of a note into cash and common stock (excluding an exchange with a designated financial institution in lieu of conversion, as described in &#x201c;Description of Notes&#x2014;Conversion Rights&#x2014;Exchange in Lieu of Conversion,&#x201d; which would be taxable as described above under &#x201c;&#x2014;Sale, Exchange, Redemption or Other Taxable Disposition of Notes&#x201d;) were not treated as a recapitalization as discussed above, the cash payment received (excluding cash received in lieu of a fractional share or attributable to accrued but unpaid interest) may be treated as proceeds from the redemption of a portion of the note and taxed in the manner described above under &#x201c;&#x2014;Sale, Exchange, Redemption or Other Taxable Disposition of Notes.&#x201d; In such case, our common stock received (including any fractional share deemed received) on such a conversion would be treated as received upon a conversion of the other portion of the note, which generally would not be taxable to a U.S. holder except to the extent of any cash received in lieu of a fractional share or any amounts received with respect to accrued but unpaid interest. In that case, the U.S. holder&#x2019;s adjusted tax basis in the note would generally be allocated pro rata between the portion of the note that is treated as converted into common stock (including any fractional share deemed received) and the portion of the note that is treated as sold for cash based on the fair market value of our common stock and the cash received (other than cash received in lieu of fractional shares, and excluding any amounts received treated as accrued but unpaid interest). The holding period for our common stock received in the conversion would include the holding period for the note, except that the holding period for any common stock received with respect to accrued but unpaid interest would commence on the day after our common stock is received.

Distributions

We have never declared or paid cash dividends on our common stock, and we do not anticipate paying any cash dividends in the foreseeable future. However, if we do make distributions of cash or property on our common stock (other than certain pro rata distributions of our common stock or rights to acquire common stock), such distributions will constitute ordinary dividend income for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. Amounts not treated as dividends for U.S. federal income tax purposes will constitute a return of capital and first be applied against

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and reduce a holder&#x2019;s adjusted tax basis in its common stock, but not below zero. Any excess will be treated as capital gain from the sale or exchange of such common stock. Because we may not know the extent to which a distribution is a dividend for U.S. federal income tax purposes at the time it is made, for purposes of the withholding rules discussed below we or the applicable withholding agent may treat the entire distribution as a dividend. Dividends received by a corporate U.S. holder may be eligible for a dividends received deduction, subject to applicable limitations. Dividends received by certain non-corporate U.S. holders (including individuals) are generally taxed at the lower applicable long-term capital gains rates, provided certain holding period and other requirements are satisfied.

Constructive Distributions

The conversion rate of the notes will be adjusted in certain circumstances. Adjustments (or failures to make adjustments) that have the effect of increasing, for a U.S. holder of notes, the proportionate interest in our assets or earnings and profits may, in some circumstances, result in a deemed distribution to the U.S. holder for U.S. federal income tax purposes even though no cash or property is received. Adjustments to the conversion rate made pursuant to a bona fide reasonable adjustment formula that has the effect of preventing the dilution of the interest of the holders of the notes, however, will generally not result in a deemed distribution to a U.S. holder.

Certain of the conversion rate adjustments provided in the notes (including, without limitation, adjustments in respect of taxable dividends to holders of our common stock) may not qualify as being pursuant to a bona fide reasonable adjustment formula. If such adjustments are made, a U.S. holder of notes will be deemed to have received a distribution even though the U.S. holder has not received any cash or property as a result of such conversion rate adjustment. In addition, an adjustment to the conversion rate in connection with a make-whole fundamental change may, in some circumstances, be treated as a deemed distribution. Any deemed distribution will be taxable as a dividend to the extent of our current or accumulated earnings and profits, generally as described above under &#x201c;&#x2014;Distributions.&#x201d;

However, it is unclear whether a constructive dividend deemed paid to a non-corporate U.S. holder would be eligible for the lower applicable long-term capital gains rates as described above under &#x201c;&#x2014;Distributions.&#x201d; It is also unclear whether corporate U.S. holders would be entitled to claim the dividends received deduction with respect to any such constructive dividends. Generally, a U.S. holder&#x2019;s adjusted tax basis in a note will be increased to the extent any such constructive distribution is treated as a dividend. U.S. holders should consult their tax advisors on the effect a constructive distribution may have on their notes.

We are currently required to report the amount of any deemed distributions on our website or to the IRS and holders of notes not exempt from information reporting. The IRS has issued proposed regulations addressing the amount and timing of deemed distributions, as well as obligations of withholding agents and filing and notice obligations of issuers in respect of such deemed distributions. If adopted as proposed, the regulations would generally provide that (i) the amount of a deemed distribution is the excess of the fair market value of the right to acquire stock immediately after the conversion rate adjustment over the fair market value of the right to acquire stock without the adjustment, (ii) the deemed distribution occurs at the earlier of the date the adjustment occurs under the terms of the note and the date of the actual distribution of cash or property that results in the deemed distribution, (iii) subject to certain limited exceptions, a withholding agent is required to impose any applicable withholding on deemed distributions and, if there is no associated cash payment, may withhold the required amounts from, or set off the required amounts against, payments on the notes, payments on our common stock or sales proceeds received by or other funds or assets of an investor and (iv) we are required to report the amount of any deemed distributions on our website or to the IRS and all holders of notes (including holders of notes that would otherwise be exempt from information reporting). The regulations will be effective for deemed distributions occurring on or after the date of their adoption as final regulations, but holders of notes and withholding agents may rely on the proposed regulations prior to that date under certain circumstances.

Exchange in Lieu of Conversion

If a U.S. holder surrenders notes for conversion and such notes are exchanged with a designated financial institution, as described under &#x201c;Description of Notes&#x2014;Conversion Rights&#x2014;Exchange in Lieu of Conversion,&#x201d; the U.S. holder will be required to recognize gain or loss as described under &#x201c;&#x2014;Sale, Exchange, Redemption or Other Taxable Disposition of Notes.&#x201d; In such case, the U.S. holder&#x2019;s tax basis in our common stock received will equal the

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fair market value of our common stock on the date of the exchange, and the U.S. holder&#x2019;s holding period in our common stock received will begin on the day after the date of the exchange.

Sales, Certain Redemptions or Other Taxable Dispositions of Common Stock

Upon sales, certain redemptions or other taxable dispositions of our common stock, a U.S. holder generally will recognize gain or loss equal to the difference between the amount realized and the U.S. holder&#x2019;s tax basis in our common stock. Any gain or loss recognized on a taxable disposition of common stock generally will be capital gain or loss. Such capital gain or loss will be long-term capital gain or loss if a U.S. holder&#x2019;s holding period at the time of the sale, redemption or other taxable disposition of our common stock is more than one year.

Possible Effect of a Change in Conversion Consideration

In certain situations, the notes may become convertible or exchangeable into shares of an acquirer or other consideration. Furthermore, we can undertake certain transactions (such as a merger or sale of assets) in connection with a change of control or other transaction. Depending on the circumstances, an adjustment in conversion consideration or such transactions undertaken in connection with a change of control or similar transaction could result in a deemed taxable exchange of the notes to a U.S. holder and the modified notes could be treated as newly issued at that time, potentially resulting in the recognition of taxable gain or loss. Furthermore, depending on the circumstances, the U.S. federal income tax consequences of the exchange or conversion of the notes as well as the ownership of the notes and the shares of our common stock or other consideration received upon conversion may be different from the U.S. federal income tax consequences addressed in this discussion. U.S. holders should consult their tax advisors regarding the consequences to them of such situations.

Consequences to Non-U.S. Holders

Interest on the Notes

Subject to the discussions below under &#x201c;Information Reporting and Backup Withholding&#x201d; and &#x201c;Foreign Account Tax Compliance Act,&#x201d; interest paid on a note to a non-U.S. holder that is not effectively connected with the non-U.S. holder&#x2019;s conduct of a trade or business within the United States (and, if required by an applicable income tax treaty, is not attributable to a U.S. permanent establishment or fixed base maintained by the non-U.S. holder) generally will not be subject to U.S. federal income or withholding tax of 30%, provided that:

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the non-U.S. holder does not actually or constructively own (pursuant to the conversion feature of the notes or otherwise) 10% or more of the total combined voting power of all classes of our stock that are entitled to vote;
&#x2022;
the non-U.S. holder is not a controlled foreign corporation that is related to us (actually or constructively) through stock ownership; and
&#x2022;
the non-U.S. holder (a) provides its name and address, and certifies, under penalties of perjury, that it is not a U.S. person (which certification may be made on an IRS Form W-8BEN or W-8BEN-E (or other applicable form)) or (b) holds the notes through certain foreign intermediaries and the non-U.S. holder and the foreign intermediaries satisfy the certification requirements of applicable Treasury regulations.

If a non-U.S. holder cannot satisfy the requirements described above, payments of interest will be subject to a U.S. federal withholding tax at a 30% rate, unless the non-U.S. holder provides the applicable withholding agent with a properly executed (i) IRS Form W-8BEN or W-8BEN-E (or other applicable form) claiming an exemption from or reduction in withholding under an applicable income tax treaty or (ii) IRS Form W-8ECI (or other applicable form) stating that interest paid on the notes is not subject to withholding tax because it is effectively connected with the non-U.S. holder&#x2019;s conduct of a trade or business in the United States. If a non-U.S. holder is engaged in a trade or business in the United States and interest on a note is effectively connected with the conduct of that trade or business (and, if required by an applicable income tax treaty, is attributable to a U.S. permanent establishment or fixed base maintained by the non-U.S. holder), then (although the non-U.S. holder will be exempt from the 30% withholding tax

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provided the certification requirements discussed above are satisfied) the non-U.S. holder will be subject to U.S. federal income tax on that interest on a net income basis generally in the same manner as if the non-U.S. holder were a U.S. holder. In addition, if the non-U.S. holder is a foreign corporation, it may be subject to a branch profits tax equal to 30% (or lesser rate under an applicable income tax treaty) of its earnings and profits for the taxable year, subject to adjustments, that are effectively connected with its conduct of a trade or business in the United States.

Dividends and Constructive Distributions

Subject to the discussion below on effectively connected income, dividends paid to a non-U.S. holder (and any deemed dividends resulting from certain adjustments, or failures to make adjustments, to the conversion rate of the notes, see above under &#x201c;&#x2014;Consequences to U.S. Holders&#x2014;Constructive Distributions&#x201d;), will be subject to U.S. federal withholding tax at a rate of 30% of the gross amount of the dividends or deemed dividends (or such lower rate specified by an applicable income tax treaty, provided the non-U.S. holder furnishes a valid IRS Form W-8BEN or W-8BEN-E (or other applicable documentation) certifying qualification for the lower treaty rate). A non-U.S. holder that does not timely furnish the required documentation, but that qualifies for a reduced treaty rate, may obtain a refund of any excess amounts withheld by timely filing an appropriate claim for refund with the IRS. Non-U.S. holders should consult their tax advisors regarding their entitlement to benefits under any applicable income tax treaty. Any applicable withholding taxes (including backup withholding) with respect to deemed dividends may be withheld from or set off against interest and payments upon conversion, repurchase, redemption or maturity of the notes or, in some circumstances, any payments on our common stock or sales proceeds received by or other funds or assets of such non-U.S. holder.

If dividends (or deemed dividends) paid to a non-U.S. holder are effectively connected with the non-U.S. holder&#x2019;s conduct of a trade or business within the United States (and, if required by an applicable income tax treaty, is attributable to a U.S. permanent establishment or fixed base maintained by the non-U.S. holder), the non-U.S. holder will be exempt from the U.S. federal withholding tax described above. To claim the exemption, the non-U.S. holder must furnish to the applicable withholding agent a valid IRS Form W-8ECI, certifying that the dividends (or deemed dividends) are effectively connected with the non-U.S. holder&#x2019;s conduct of a trade or business within the United States.

Any such effectively connected dividends (or deemed dividends) will be subject to U.S. federal income tax on a net income basis at the regular rates. A non-U.S. holder that is a corporation also may be subject to a branch profits tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on such effectively connected dividends (or deemed dividends), as adjusted for certain items. Non-U.S. holders should consult their tax advisors regarding any applicable tax treaties that may provide for different rules.

Sale, Exchange, Certain Redemptions, Conversion or Other Taxable Disposition of Notes or Common Stock

Subject to the discussion below under &#x201c;Information Reporting and Backup Withholding&#x2014;Non-U.S. Holders&#x201d; and &#x201c;Foreign Account Tax Compliance Act,&#x201d; any gain recognized by a non-U.S. holder on the sale, exchange (including an exchange with a designated financial institution in lieu of conversion, as described in &#x201c;Description of Notes&#x2014;Conversion Rights&#x2014;Exchange in Lieu of Conversion&#x201d;), certain redemptions, conversion or other taxable dispositions of a note or common stock will not be subject to U.S. federal income tax unless:

&#x2022;
the gain is effectively connected with the non-U.S. holder&#x2019;s conduct of a trade or business within the United States (and, if required by an applicable income tax treaty, is attributable to a U.S. permanent establishment or fixed base maintained by the non-U.S. holder);
&#x2022;
the non-U.S. holder is a nonresident alien individual present in the United States for 183 days or more during the taxable year of the disposition and certain other requirements are met; or
&#x2022;
our notes or common stock constitutes a United States real property interest (a &#x201c;USRPI&#x201d;) by reason of our status as a United States real property holding corporation (a &#x201c;USRPHC&#x201d;), for U.S. federal income tax purposes.

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Gain described in the first bullet point above generally will be subject to U.S. federal income tax on a net income basis at the regular rates applicable to U.S. persons. A non-U.S. holder that is a corporation also may be subject to a branch profits tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on such effectively connected gain, as adjusted for certain items. A non-U.S. holder described in the second bullet point above will be subject to U.S. federal income tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on gain realized upon the sale, exchange, redemption, conversion or other taxable dispositions of a note or common stock, which gain may be offset by certain U.S. source capital losses of the non-U.S. holder (even though the individual is not considered a resident of the United States), provided the non-U.S. holder has timely filed U.S. federal income tax returns with respect to such losses. With respect to the third bullet point above, we believe we currently are not, and do not anticipate becoming, a USRPHC.

Any amounts (including common stock) which a non-U.S. holder receives on a sale, exchange, redemption, conversion or other taxable disposition of a note which are attributable to accrued but unpaid interest will be subject to U.S. federal income or withholding tax in accordance with the rules described above under &#x201c;&#x2014;Interest on the Notes.&#x201d;

Non-U.S. holders should consult their tax advisors regarding any applicable tax treaties that may provide for different rules.

Information Reporting and Backup Withholding

U.S. Holders

Information reporting requirements generally will apply to payments of interest (including additional interest and special interest, if any), deemed dividends on the notes (if any), dividends on our common stock and the proceeds of a sale or other taxable disposition of a note or common stock paid to a U.S. holder unless the U.S. holder is an exempt recipient, and if required, certifies as to that status. Backup withholding generally will apply to those payments if the U.S. holder fails to provide an appropriate certification with its correct taxpayer identification number or otherwise establish an exemption. Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules will be allowed as a refund or a credit against a U.S. holder&#x2019;s U.S. federal income tax liability provided the required information is timely furnished to the IRS.

Non-U.S. Holders

Payments of interest (including additional interest and special interest, if any), deemed distributions on the notes (if any) and dividends on our common stock will not be subject to backup withholding, provided the non-U.S. holder certifies its non-U.S. status, such as by furnishing a valid IRS Form W-8BEN, W-8BEN-E or W-8ECI, or otherwise establishes an exemption. However, information returns are required to be filed with the IRS in connection with any payment of interest (including additional interest and special interest, if any), deemed distributions on the notes (if any) and distributions on our common stock paid to the non-U.S. holder, regardless of whether such distributions (or deemed distributions) constitute dividends or whether any tax was actually withheld. In addition, proceeds of the sale or other taxable disposition of our notes or common stock within the United States or conducted through certain U.S.-related brokers generally will not be subject to backup withholding or information reporting if the applicable withholding agent receives the certification described above or the non-U.S. holder otherwise establishes an exemption. Proceeds of a disposition of our notes or common stock conducted through a non-U.S. office of a non-U.S. broker that does not have certain enumerated relationships with the United States generally will not be subject to backup withholding or information reporting.

Copies of information returns that are filed with the IRS may also be made available under the provisions of an applicable treaty or agreement to the tax authorities of the country in which the non-U.S. holder resides or is established.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against a non-U.S. holder&#x2019;s U.S. federal income tax liability, provided the required information is timely furnished to the IRS.

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Foreign Account Tax Compliance Act

Withholding taxes may be imposed under Sections 1471 to 1474 of the Code (such Sections commonly referred to as the Foreign Account Tax Compliance Act, or &#x201c;FATCA&#x201d;) on certain types of payments made to non-U.S. financial institutions and certain other non-U.S. entities. Specifically, a 30% withholding tax may be imposed on interest and dividends (including deemed dividends) on, or (subject to the proposed Treasury Regulations discussed below) gross proceeds from the sale or other disposition of, debt obligations or common stock in a U.S. corporation paid to a &#x201c;foreign financial institution&#x201d; or a &#x201c;non-financial foreign entity&#x201d; (each as defined in the Code), unless (1) the foreign financial institution undertakes certain diligence and reporting obligations, (2) the non-financial foreign entity either certifies it does not have any &#x201c;substantial United States owners&#x201d; (as defined in the Code) or furnishes identifying information regarding each substantial United States owner, or (3) the foreign financial institution or non-financial foreign entity otherwise qualifies for an exemption from these rules. If the payee is a foreign financial institution and is subject to the diligence and reporting requirements in (1) above, it must enter into an agreement with the U.S. Department of the Treasury requiring, among other things, that it undertake to identify accounts held by certain &#x201c;specified United States persons&#x201d; or &#x201c;United States owned foreign entities&#x201d; (each as defined in the Code), annually report certain information about such accounts, and withhold 30% on certain payments to non-compliant foreign financial institutions and certain other account holders. Foreign financial institutions located in jurisdictions that have an intergovernmental agreement with the United States governing FATCA may be subject to different rules.

Under the applicable Treasury regulations and administrative guidance, withholding under FATCA generally applies to payments of interest and dividends (including deemed dividends) regardless of when they are made (or deemed made). While withholding under FATCA would have applied also to payments of gross proceeds from the sale or other disposition of our notes or common stock, proposed Treasury regulations eliminate FATCA withholding on payments of gross proceeds entirely. Taxpayers generally may rely on these proposed Treasury regulations until final Treasury regulations are issued.

Prospective investors should consult their tax advisors regarding the potential application of withholding under FATCA to their investment in the notes and our common stock.

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The Concurrent Common Stock Offering

Concurrently with this offering, we are offering, pursuant to a separate prospectus supplement, shares of our common stock, which we refer to as the &#x201c;concurrent common stock offering.&#x201d; We have granted the underwriters of the concurrent common stock offering a 30-day option to purchase up to an additional shares of our common stock. We estimate that the net proceeds to us from the concurrent common stock offering, if it is consummated, will be approximately $ million (or approximately $ million if the underwriters of the concurrent common stock offering exercise in full their option to purchase additional shares of common stock), after deducting the underwriting discounts and commissions and our estimated offering expenses.

The completion of this offering is not contingent on the completion of the concurrent common stock offering, and the completion of the concurrent common stock offering is not contingent on the completion of this offering. Accordingly, you should not assume that the concurrent common stock offering will be consummated on the terms described in this prospectus supplement, if at all, or that we will receive any additional proceeds from the concurrent common stock offering. This prospectus supplement does not constitute an offer to sell, or the solicitation of an offer to buy, any securities being offered in the concurrent common stock offering. The prospectus supplement for the concurrent common stock offering does not constitute an offer to sell, or the solicitation of an offer to buy, any of the notes, or the shares of common stock, if any, issuable upon conversion of the notes, that we are offering pursuant to this prospectus supplement.

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Underwriting

Under the terms and subject to the conditions in an underwriting agreement dated the date of this prospectus supplement, the underwriters named below, for whom Morgan Stanley & Co. LLC and J.P. Morgan Securities LLC are acting as representatives, have severally agreed to purchase, and we have agreed to sell to them, severally, the principal amount of notes indicated below:

Name

Principal Amount of Notes

Morgan Stanley & Co. LLC

J.P. Morgan Securities LLC

Total:

The underwriters and the representatives are collectively referred to as the &#x201c;underwriters&#x201d; and the &#x201c;representatives,&#x201d; respectively. The underwriters are offering the notes subject to their acceptance of the notes from us and subject to prior sale. The underwriting agreement provides that the obligations of the several underwriters to pay for and accept delivery of the notes offered by this prospectus supplement are subject to the approval of certain legal matters by their counsel and to certain other conditions. The underwriters are obligated to take and pay for all of the notes offered by this prospectus supplement if any such notes are taken. However, the underwriters are not required to take or pay for the notes covered by the underwriters&#x2019; option to purchase additional notes described below.

The underwriters initially propose to offer the notes directly to the public at the offering price listed on the cover page of this prospectus supplement or to certain dealers at a price that price less a concession not in excess of % of the principal amount of the notes. After the initial offering of the notes, the offering price and other selling terms may from time to time be varied by the representatives.

We have granted to the underwriters an option, exercisable for 30 days from the date of this prospectus supplement, to purchase up to an additional $ principal amount of the notes at the offering price listed on the cover page of this prospectus supplement, less underwriting discounts and commissions. The underwriters may exercise the option solely for the purpose of covering over-allotments, if any. To the extent the option is exercised, each underwriter will become obligated, subject to certain conditions, to purchase an additional aggregate principal amount of notes approximately proportionate to that underwriter&#x2019;s initial purchase commitment. Any notes issued or sold under the option will be issued or sold on the same terms and conditions as the other notes that are the subject of this offering.

The following table shows the underwriting discounts and commissions that we are to pay to the underwriters in connection with this offering (expressed as a percentage of the principal amount of notes). These amounts are shown assuming both no exercise and full exercise of the underwriters&#x2019; over-allotment option.

Paid by Us

No Exercise

Full
Exercise

Per Note

%

%

Total

$

$

The estimated offering expenses payable by us, exclusive of the underwriting discounts and commissions, are approximately $ . We have agreed to reimburse the underwriters for their expenses in an amount up to $25,000.

The notes are a new issue of securities, and there is currently no established trading market for such notes. We do not intend to apply for the notes to be listed on any securities exchange or to arrange for the notes to be quoted on any quotation system.

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Certain of the underwriters have advised us that they intend to make a market in the notes, but they are not obligated to do so and they may discontinue any market-making in the notes at any time in their sole discretion without notice. Accordingly, we cannot assure you that a liquid trading market will develop for the notes. If an active trading market for the notes does not develop, the market price and liquidity of the notes may be adversely affected. If the notes are traded, they may trade at a discount from their initial public offering price depending on prevailing interest rates, the market for similar securities, our performance and other factors.

We have agreed with each underwriter that, without the prior written consent of Morgan Stanley & Co. LLC and J.P. Morgan Securities LLC on behalf of the underwriters, we will not, and will not publicly disclose an intention to, during the period ending 60 days after the date of this prospectus supplement, or the Restricted Period:

&#x2022;
offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of our common stock or any securities convertible into or exercisable or exchangeable for our common stock, make any short sale or otherwise transfer or dispose of, directly or indirectly, including any sales pursuant to the Sales Agreement, or file or confidentially submit with the SEC a registration statement under the Securities Act relating to, any securities of our Company that are substantially similar to the shares offered in this offering, including but not limited to any options or warrants to purchase shares of our common stock or any securities that are convertible into or exchangeable for, or that represent the right to receive, shares of our common stock, or any such substantially similar securities, or publicly disclose the intention to make any offer, sale, pledge, disposition or filing; or
&#x2022;
enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the shares of our common stock, or any such other securities,

whether any such transaction described above is to be settled by delivery of shares of our common stock or such other securities, in cash or otherwise (other than (A) the notes to be sold to the underwriters in this offering and any shares to be issued upon conversion of such notes, (B) the shares to be sold in the concurrent common stock offering, (C) the issuance of options, restricted stock units, warrants or other equity awards to acquire shares of our common stock granted pursuant to our stock plans that are described in this prospectus supplement or the accompanying base prospectus, as such plans may be amended, (D) the issuance of shares of our common stock upon the exercise or vesting of any such options, restricted stock units, warrants or other equity awards to acquire shares of our common stock, (E) shares of our common stock issued upon the exercise of outstanding warrants, (F) the filing of one or more registration statements on Form S-8 registering securities pursuant to our stock plans, (G) the issuance of any shares of our common stock or any security convertible into or exercisable for shares of our common stock issued by us in connection with a joint venture or other strategic commercial transaction not primarily intended to raise capital between our Company and an unaffiliated third party; and provided that, in the case of clause (G), the aggregate number of shares of our common stock that we may sell or issue or agree to sell or issue pursuant to clause (G) shall not exceed 5% of the total number of shares of our common stock issued and outstanding immediately following the completion of the transactions contemplated by this offering), and provided, further, that any newly appointed director or executive officer that is appointed during the Restricted Period that is a recipient of shares of our common stock or securities convertible into or exercisable for our common stock pursuant to this clause (G) shall execute and deliver to Morgan Stanley & Co. LLC and J.P. Morgan Securities LLC a lock-up agreement covering the remainder of the Restricted Period, (H) facilitating the establishment of a trading plan on behalf of a stockholder, officer or director of our Company pursuant to Rule 10b5-1 under the Exchange Act for the transfer of shares of our common stock, provided that (i) such plan for any executive officer or director does not provide for the transfer of our common stock during the Restricted Period and (ii) to the extent a public announcement or filing under the Exchange Act, if any, is required of us regarding the establishment of such plan, such required announcement or filing shall include a statement to the effect that no transfer of our common stock may be made under such plan during the Restricted Period, and no other public announcement shall be made voluntarily, and (I) the registration, sale and issuance of shares of our common stock in connection with an &#x201c;at-the-market&#x201d; equity offering program, provided that no sales or issuances shall be made pursuant to any such program for 30 calendar days following the settlement of notes for this offering.

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Our directors and officers have agreed that, without the prior written consent of Morgan Stanley & Co. LLC and J.P. Morgan Securities LLC on behalf of the underwriters, they will not, and will not publicly disclose an intention to, during the Restricted Period:

&#x2022;
offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of our common stock beneficially owned (as such term is used in Rule 13d-3 of the Exchange Act), by such lock-up party or any other securities so owned convertible into or exercisable or exchangeable for shares of our common stock, or the lock-up securities;
&#x2022;
enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the shares of our common stock;

whether any such transaction described above is to be settled by delivery of shares of our common stock or such other securities, in cash or otherwise. The foregoing precludes the lock-up party from engaging in any hedging or other transactions designed or intended, or which could reasonably be expected to lead to or result in, a sale or disposition of any shares of our common stock, or securities convertible into or exercisable or exchangeable for shares of our common stock, even if any such sale or disposition transaction or transactions would be made or executed by or on behalf of someone other than the lock-up party.

The restrictions described in the immediately preceding paragraph shall not apply to:

(1) the receipt of any grant, or exercise, by the lock-up party of any option, restricted stock unit award, warrant or other right to acquire any shares of our common stock or options to purchase shares of our common stock or any security convertible into or exercisable for shares of our common stock in accordance with their terms, pursuant to any stock option, stock bonus, equity incentive or other stock plan or arrangement; provided that the underlying shares shall continue to be subject to the restrictions on transfer set forth in the lock-up agreement, and provided further that any filing under Section 16(a) of the Exchange Act with regard to this clause shall clearly indicate in the footnotes thereto that the filing relates to the circumstances described in this provision and no public filing, report or announcement shall be voluntarily made;

(2) any transfer of lock-up securities for bona fide financial and estate planning purposes, including, but not limited to, transfers to the immediate family of the lock-up party or to any trust, partnership, limited liability company or other legal entity commonly used for estate planning purposes, for the direct or indirect benefit of the lock-up party or the immediate family of the lock-up party;

(3) if the lock-up party is a trust, to the beneficiary of such trust;

(4) any bona fide gift;

(5) any transfer of lock-up securities by will or intestate succession;

(6) any distribution or other transfer by a partnership to its partners or former partners or by a limited liability company to its members or retired members or by a corporation to its stockholders or former stockholders or to any wholly-owned subsidiary of such corporation;

(7) transfers or dispositions of shares of our common stock to any corporation, partnership, limited liability company or other entity all of the beneficial ownership interests which are held by the lock-up party and/or the immediate family of the lock-up party;

(8) any transfer in connection with a sale, merger or transfer of all or substantially all of the assets of the lock-up party or any other change of control of the lock-up party, not undertaken for the purpose of avoiding the restrictions imposed by the lock-up agreement; provided that in the event that such transaction is not completed, the lock-up securities shall remain subject to the restrictions set forth in the lock-up agreement;

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(9) any transfer to the lock-up party&#x2019;s affiliates (as defined in Rule 405 promulgated under the Securities Act) or to any investment fund or other entity controlled or managed by the lock-up party;

(10) any transfer by operation of law, such as pursuant to a qualified domestic relations order or in connection with a divorce settlement;

(11) any shares of our common stock or our other securities acquired in open market transactions after completion of this offering; provided that, no filing by any party under the Exchange Act or other public announcement shall be required or shall be voluntarily made in connection with such transfer;

(12) any transfer of lock-up securities pursuant to a bona fide third-party tender offer, merger, consolidation, liquidation or other similar transaction made to all holders of our capital stock involving a change of control of our Company; provided that (i) the per-share consideration for the lock-up securities transferred as described above shall be greater than the public offering price per share in this offering, (ii) all lock-up securities subject to the lock-up agreement that are not so transferred, sold, tendered or otherwise disposed of remain subject to the lock-up agreement and (iii) it shall be a condition of transfer, sale, tender or other disposition that if such tender offer, merger, consolidation or other such transaction is not completed, the lock-up party&#x2019;s lock-up securities shall remain subject to the restrictions set forth in the lock-up agreement;

(13) any transfer of lock-up securities to us as forfeitures or other transfers, sales or dispositions to satisfy tax withholding obligations of the lock-up party in connection with the vesting or exercise of equity awards or similar rights to purchase shares of our common stock or any securities convertible into or exercisable or exchangeable for shares of our common stock pursuant to our equity incentive plans or outstanding warrants; provided that any lock-up securities acquired in connection with such vesting or exercise of equity awards or warrants described in this clause shall be subject to the restrictions set forth in the lock-up agreement;

(14) any transfer of lock-up securities to us pursuant to an exercise, including a net exercise or cashless exercise, by the lock-up party of outstanding equity awards pursuant to our equity incentive plans or outstanding warrants; provided that any lock-up securities acquired upon the net exercise or cashless exercise of equity awards described in this clause shall be subject to the restrictions set forth in the lock-up agreement;

(15) in connection with sales of the lock-up party&#x2019;s shares of our common stock made pursuant to a 10b5-1 trading plan, or 10b5-1 trading plan that is designed to comply with Rule 10b5-1 under the Exchange Act (as such rule was in effect at the time any such trading plan was adopted) that has been entered into by the lock-up party prior to the date of the lock-up agreement and provided to Morgan Stanley & Co. LLC, J.P. Morgan Securities LLC and their counsel, provided that to the extent a public announcement or filing under the Exchange Act, if any, is required of the lock-up party or our Company regarding any such sales, such announcement or filing shall include a statement to the effect that any sales were effected pursuant to such 10b5-1 trading plan and no other public announcement shall be made voluntarily in connection with such sales; or

(16) any transfer in connection with the repurchase of the lock-up securities or other securities by us pursuant to agreements providing for the right of said repurchase in connection with the termination of the lock-up party&#x2019;s employment or consulting service with us;

provided that in the case of any transfer, gift or other disposition pursuant to clauses (2), (3), (4), (5), (6), (7), (8), (9) or (10) above, the transferee, trust, donee or other recipient agrees to be bound in writing by the terms of the lock-up agreement prior to such transfer and no filing by any party (donor, donee, transferor or transferee) under the Exchange Act shall be required or shall be voluntarily made in connection with such transfer (other than required filings under Section 16(a) and Section 13(d) or 13(g) of the Exchange Act, and any filings made after the expiration of the Restricted Period); and provided further that in the case of clauses (13) or (14) above, any report filed by the lock-up party in connection with such transactions under Section 16(a) of the Exchange Act shall include a statement in such report to the effect that the purpose of such transfer was either (A) to cover tax withholding obligations of the lock-up party in connection with such vesting or exercise, or (B) in connection with a cashless or net exercise of equity awards.

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Notwithstanding anything herein to the contrary, nothing herein shall prevent the lock-up party from establishing a 10b5-1 trading plan or from amending an existing 10b5-1 trading plan so long as there are no sales of lock-up securities under such new plan or amended plan during the Restricted Period.

In addition, each lock-up party agrees that, without the prior written consent of Morgan Stanley & Co. LLC and J.P. Morgan Securities LLC on behalf of the underwriters, the lock-up party will not, and will not publicly disclose an intention to, during the Restricted Period, make any demand for, or exercise any right with respect to, the registration of any shares of our common stock or any security convertible into or exercisable or exchangeable for shares of our common stock. The lock-up party agrees and consents to the entry of stop transfer instructions with our transfer agent and registrar against the transfer of their shares of our common stock except in compliance with the foregoing restrictions.

In order to facilitate this offering, the underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the common stock or the notes. Specifically, the underwriters may sell more notes than they are obligated to purchase under the underwriting agreement, creating a short position. A short sale is covered if the short position is no greater than the principal amount of notes available for purchase by the underwriters under the option to purchase additional notes. The underwriters can close out a covered short sale by exercising the option to purchase additional notes or purchasing notes in the open market. In determining the source of notes to close out a covered short sale, the underwriters will consider, among other things, the open market price of the notes compared to the price available under the option to purchase additional notes. The underwriters may also sell notes in excess of the option, creating a naked short position. The underwriters must close out any naked short position by purchasing notes in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of the notes in the open market after pricing that could adversely affect investors who purchase in this offering. As an additional means of facilitating this offering, the underwriters may bid for, and purchase, shares of common stock or the notes in the open market to stabilize the price of the common stock or notes. These activities may raise or maintain the market price of the common stock or notes above independent market levels or prevent or retard a decline in the market price of the common stock and/or the notes. The underwriters are not required to engage in these activities and may end any of these activities at any time.

We and the underwriters have agreed to indemnify each other against certain liabilities, including liabilities under the Securities Act.

A prospectus supplement in electronic format may be made available on websites maintained by one or more underwriters, or selling group members, if any, participating in this offering. The representatives may agree to allocate a portion of the aggregate principal amount of notes to underwriters for sale to their online brokerage account holders. Internet distributions will be allocated by the representatives to underwriters that may make Internet distributions on the same basis as other allocations.

The underwriters and their respective affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. Certain of the underwriters and their respective affiliates have, from time to time, performed, and may in the future perform, various financial advisory and investment banking services for us, for which they received or will receive customary fees and expenses. For example, certain of the underwriters in this offering are also acting as underwriters in the concurrent common stock offering.

In addition, in the ordinary course of their various business activities, the underwriters and their respective affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers and may at any time hold long and short positions in such securities and instruments. Such investment and securities activities may involve our securities and instruments. The underwriters and their respective affiliates may also make investment recommendations or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long or short positions in such securities and instruments.

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Concurrent Common Stock Offering

Concurrently with this offering, we are conducting a public offering of shares of our common stock (or up to shares of our common stock if the underwriters in the concurrent common stock offering exercise in full their option to purchase additional shares of common stock). Neither this offering nor the concurrent common stock offering is conditioned upon the completion of the other, so it is possible that this offering occurs and the concurrent common stock offering does not occur, or vice versa. We cannot assure you that the concurrent common stock offering will be completed on the terms described herein, on significantly different terms or at all. The concurrent common stock offering is being made pursuant to a separate prospectus supplement and nothing contained herein shall constitute an offer to sell or the solicitation of an offer to buy our common stock to be issued in the concurrent common stock offering.

Selling Restrictions

Notice to Prospective Investors in the European Economic Area

The notes are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the European Economic Area (&#x201c;EEA&#x201d;) or in the United Kingdom. For these purposes, a retail investor means a person who is one (or more) of: (i) a retail client as defined in point (11) of Article 4(1) of Directive 2014/65/EU (as amended, &#x201c;MiFID II&#x201d;); or (ii) a customer within the meaning of Directive 2016/97 (as amended, the &#x201c;Insurance Distribution Directive&#x201d;), where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or (iii) not a qualified investor as defined in Directive 2017/1129 (as amended or superseded, the &#x201c;Prospectus Regulation&#x201d;). Consequently no key information document required by Regulation (EU) No 1286/2014 (as amended, the &#x201c;PRIIPs Regulation&#x201d;) for offering or selling the notes or otherwise making them available to retail investors in the EEA has been prepared and therefore offering or selling the notes or otherwise making them available to any retail investor in the EEA may be unlawful under the PRIIPS Regulation. This prospectus supplement has been prepared on the basis that any offer of notes in any Member State of the EEA will be made pursuant to an exemption under the Prospectus Regulation, from the requirement to publish a prospectus for offers of notes. This prospectus supplement is not a prospectus for the purposes of the Prospectus Regulation.

Notice to Prospective Investors in the United Kingdom

The notes are not intended to be offered, sold, distributed or otherwise made available to and should not be offered, sold, distributed or otherwise made available to any retail investor in the United Kingdom (the &#x201c;U.K.&#x201d;). For these purposes, a &#x201c;retail investor&#x201d; means a person who is either one (or both) of the following: (i) not a professional client, as defined in point (8) of Article 2(1) of Regulation (EU) No 600/2014 as it forms part of domestic law by virtue of the European Union (Withdrawal) Act 2018 (&#x201c;EUWA&#x201d;); or (ii) not a &#x201c;qualified investor&#x201d; as defined in Paragraph 15 of Schedule 1 to the Public Offers and Admissions to Trading regulations 2024 (the &#x201c;POATRs&#x201d;). Consequently no disclosure document required by the FCA Product Disclosure Sourcebook (&#x201c;DISC&#x201d;) for offering, selling or distributing the notes or otherwise making them available to retail investors in the U.K. has been prepared and therefore offering, selling or distributing the notes or otherwise making them available to any retail investor in the U.K. may be unlawful under DISC and the Consumer Composite Investments (Designated Activities) Regulation 2024.

Notice to Prospective Investors in Canada

The notes may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions, and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the securities must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

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Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus supplement (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser&#x2019;s province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser&#x2019;s province or territory for particulars of these rights or consult with a legal advisor.

Pursuant to section 3A.3 (or, in the case of securities issued or guaranteed by the government of a non-Canadian jurisdiction, section 3A.4) of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

Notice to Prospective Investors in Switzerland

This prospectus supplement is not intended to constitute, and does not constitute, an offer to the public or a solicitation to purchase or invest in the notes described herein.

The notes have not been and will not be publicly offered, directly or indirectly, in Switzerland, within the meaning of the Swiss Financial Services Act (&#x201c;FinSA&#x201d;) except to any investor that qualifies as a professional client within the meaning of FinSA.

The notes have not been and shall not be admitted to any trading venue (exchange or multilateral trading facility) in Switzerland.

Neither this prospectus supplement nor any other offering or marketing material relating to the notes (x) constitutes a prospectus pursuant to article 35 of FinSA for a public offering of the notes in Switzerland and no such prospectus has been or will be prepared for or in connection with the offering of the notes in Switzerland or (y) has been or will be filed with or approved by a Swiss review body (Pr&uuml;fstelle) pursuant to article 52 of FinSA.

Neither this prospectus supplement nor any other offering or marketing material relating to the notes may be publicly distributed or otherwise made publicly available in Switzerland.

Notice to Prospective Investors in the Dubai International Financial Centre (DIFC)

The notes have not been, and will not be, offered to any person in the DIFC unless such offer is:
(i)
an &#x201c;Exempt Offer&#x201d; in accordance with the Markets Rules (MKT) Module of the Dubai Financial Services Authority (the &#x201c;DFSA&#x201d;) rulebook; and
(ii)
made only to persons who meet the Professional Client criteria set out in Rule 2.3.3 of the Conduct of Business (COB) Module of the DFSA rulebook.

Notice to Prospective Investors in Hong Kong

No securities have been offered or sold, and no securities may be offered or sold, in Hong Kong, by means of any document, other than to persons whose ordinary business is to buy or sell shares or debentures, whether as principal or agent; or to &#x201c;professional investors&#x201d; as defined in the Securities and Futures Ordinance (Cap. 571) of Hong Kong (&#x201c;SFO&#x201d;) and any rules made under that Ordinance; or in other circumstances which do not result in the document being a &#x201c;prospectus&#x201d; as defined in the Companies Ordinance (Cap. 32) of Hong Kong (&#x201c;CO&#x201d;) or which do not constitute an offer or invitation to the public for the purpose of the CO or the SFO. No document, invitation or advertisement relating to the securities has been issued or may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted under the securities laws of

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Hong Kong) other than with respect to securities which are or are intended to be disposed of only to persons outside Hong Kong or only to &#x201c;professional investors&#x201d; as defined in the SFO and any rules made under that Ordinance.

This prospectus supplement has not been registered with the Registrar of Companies in Hong Kong. Accordingly, this prospectus supplement may not be issued, circulated or distributed in Hong Kong, and the securities may not be offered for subscription to members of the public in Hong Kong. Each person acquiring the securities will be required, and is deemed by the acquisition of the securities, to confirm that he is aware of the restriction on offers of the securities described in this prospectus supplement and the relevant offering documents and that he is not acquiring, and has not been offered any securities in circumstances that contravene any such restrictions.

Notice to Prospective Investors in Japan

The offering has not been and will not be registered under the Financial Instruments and Exchange Act of Japan (Act No. 25 of 1948 of Japan, as amended, the &#x201c;FIEA&#x201d;), and the Initial Purchaser will not offer or sell any securities, directly or indirectly, in Japan or to, or for the benefit of, any resident of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan or to, or for the benefit of, any resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the FIFA and any other applicable laws, regulations and ministerial guidelines of Japan.

Notice to Prospective Investors in Singapore

This prospectus supplement has not been and will not be lodged or registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus supplement and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the Notes may not be circulated or distributed, nor may the notes be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to any person in Singapore other than (i) to an institutional investor (as defined in Section 4A of the SFA) pursuant to Section 274 of the SFA or (ii) to an accredited investor (as defined in Section 4A of the SFA) pursuant to and in accordance with the conditions specified in Section 275 of the SFA and (where applicable) Regulation 3 of the Securities and Futures (Classes of Investors) Regulations 2018.

Any reference to the &#x201c;SFA&#x201d; is a reference to the Securities and Futures Act 2001 of Singapore, as modified or amended from time to time and a reference to any term as defined in the SFA or any provision in the SFA is a reference to that term or provision as modified or amended from time to time including by such of its subsidiary legislation as may be applicable at the relevant time.

Notice to Prospective Investors in Israel

The notes offered by this document have not been approved or disapproved by the Israel Securities Authority (the &#x201c;ISA&#x201d;), nor have such notes been registered for sale in Israel. The notes may not be offered or sold, directly or indirectly, to the public in Israel, absent the publication of a prospectus that has been approved by the ISA. The ISA has not issued permits, approvals or licenses in connection with this offering or publishing this document, nor has it authenticated the details included herein, confirmed their reliability or completeness, or rendered an opinion as to the quality of the notes being offered.

This document does not constitute a prospectus under the Israeli Securities Law, 5728-1968 (the &#x201c;Israeli Securities Law&#x201d;), and has not been filed with or approved by the ISA. In Israel, this prospectus is being distributed only to, and is directed only at, and any offer of the notes is directed only at, (i) a limited number of persons in accordance with the Israeli Securities Law and (ii) investors listed in the first addendum (the &#x201c;Addendum&#x201d;) to the Israeli Securities Law, consisting primarily of joint investment in trust funds, provident funds, insurance companies, banks, portfolio managers, investment advisors, members of the Tel Aviv Stock Exchange, underwriters, venture capital funds, entities with equity in excess of NIS 50 million and &#x201c;qualified individuals,&#x201d; each as defined in the Addendum (as it may be amended from time to time), collectively referred to as qualified investors (in each case, purchasing for their own

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account or, where permitted under the Addendum, for the accounts of their clients who are investors listed in the Addendum). Qualified investors are required to submit written confirmation that they fall within the scope of the Addendum, are aware of the meaning of same and agree to it.

Notice to Prospective Investors in Australia

This prospectus supplement and the accompanying prospectus:

&#x2022;
do not constitute a disclosure document or a prospectus under Chapter 6D.2 of the Corporations Act 2001 (Cth), or the Corporations Act;
&#x2022;
have not been, and will not be, lodged with the Australian Securities and Investments Commission, or the ASIC, as a disclosure document for the purposes of the Corporations Act and does not purport to include the information required of a disclosure document for the purposes of the Corporations Act; and
&#x2022;
may only be provided in Australia to select investors who are able to demonstrate that they fall within one or more of the categories of investors, available under section 708 of the Corporations Act, or Exempt Investors.

The notes may not be directly or indirectly offered for subscription or purchased or sold, and no invitations to subscribe for or buy the notes may be issued, and no draft or definitive offering memorandum, advertisement or other offering material relating to any securities may be distributed in Australia, except where disclosure to investors is not required under Chapter 6D of the Corporations Act or is otherwise in compliance with all applicable Australian laws and regulations. By submitting an application for the notes, you represent and warrant to us that you are an Exempt Investor.

As any offering of notes under this prospectus supplement and the accompanying prospectus will be made without disclosure in Australia under Chapter 6D.2 of the Corporations Act, the offer of those securities for resale in Australia within 12 months may, under section 707 of the Corporations Act, require disclosure to investors under Chapter 6D.2 if none of the exemptions in section 708 applies to that resale. By applying for the securities you undertake to us that you will not, for a period of 12 months from the date of issue of the securities, offer, transfer, assign or otherwise alienate those securities to investors in Australia except in circumstances where disclosure to investors is not required under Chapter 6D.2 of the Corporations Act or where a compliant disclosure document is prepared and lodged with ASIC.

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Legal Matters

The validity of the issuance of the notes offered by this prospectus supplement will be passed upon for us by Paul Hastings LLP, Palo Alto, California. Latham & Watkins LLP, Costa Mesa, California, is counsel to the underwriters in connection with this offering.

Experts

The consolidated financial statements of Viking Therapeutics, Inc. and Subsidiaries as of December 31, 2025 and for the year then ended, incorporated in this prospectus supplement by reference from Viking Therapeutics, Inc.&#x2019;s Annual Report on Form 10&#x2011;K for the year ended December 31, 2025, have been audited by CBIZ CPAs P.C., an independent registered public accounting firm, as stated in its report thereon, and are incorporated herein by reference in reliance upon such report and upon the authority of such firm as experts in auditing and accounting.

The consolidated financial statements of Viking Therapeutics, Inc. and Subsidiaries as of December 31, 2024 and for the two years in the period then ended, incorporated in this prospectus supplement by reference from Viking Therapeutics, Inc.&#x2019;s Annual Report on Form 10&#x2011;K for the year ended December 31, 2025, have been audited by Marcum LLP, an independent registered public accounting firm, as stated in its report thereon, and are incorporated herein by reference in reliance upon such report and upon the authority of such firm as experts in auditing and accounting.

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Information Incorporated by Reference

The SEC allows us to incorporate by reference the information and reports we file with it, which means that we can disclose important information to you by referring you to these documents. The information incorporated by reference is an important part of this prospectus supplement. We are incorporating by reference the documents listed below, which we have already filed with the SEC:

(b)
the information specifically incorporated by reference into our Annual Report on Form 10-K for the fiscal year ended December 31, 2025 from our Definitive Proxy Statement on Schedule 14A, filed with the SEC on April 1, 2026;
(e)
our Current Reports on Form 8-K filed with the SEC on May 26, 2026 and September 22, 2026; and
(f)
the description of our common stock set forth in our Registration Statement on Form 8-A (File No. 001-37355), filed with the SEC on April 23, 2015, including any amendments or reports filed for the purpose of updating such description, including the description of common stock contained in Exhibit 4.2 of our Annual Report on Form 10-K for the fiscal year ended December 31, 2022, filed with the SEC on February 10, 2023.

All documents we file pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act on or after the date of this prospectus supplement and before the later of (1) the completion of the offering of the securities described in this prospectus supplement and (2) if applicable, the date any underwriter stops offering securities pursuant to this prospectus supplement will also be incorporated by reference in this prospectus supplement from the date of filing of such documents. Upon request, we will provide to each person, including any beneficial owner, to whom a prospectus supplement is delivered a copy of any or all of the information that has been incorporated by reference in this prospectus supplement but not delivered with this prospectus supplement.

Notwithstanding the preceding, unless specifically stated to the contrary, none of the information that we disclose under Item 2.02 or 7.01 or, if related to Items 2.02 or 7.01 or Item 9.01 of any Current Report on Form 8-K that we may, from time to time, furnish to the SEC will be incorporated by reference into, or otherwise included in, this prospectus supplement. The information contained in each of the documents incorporated by reference herein speaks only as of the date of such document. Any statement contained in a document incorporated by reference or deemed to be incorporated by reference herein, or contained in this prospectus supplement, shall be deemed to be modified or superseded for purposes of this prospectus supplement to the extent that a statement contained herein or in any subsequently filed document or report that also is incorporated by reference or is deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus supplement.

S-85

Where You Can Find More Information

We file annual, quarterly and other reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC&#x2019;s website at http://www.sec.gov. Our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, and Current Reports on Form 8-K, including any amendments to those reports, and other information that we file with or furnish to the SEC pursuant to Section 13(a) or 15(d) of the Exchange Act can also be accessed free of charge on our website at www.vikingtherapeutics.com. These website addresses, and the website addresses included in any documents incorporated by reference herein, are not intended to function as hyperlinks, and the information contained on such websites and on the SEC&#x2019;s website is not incorporated by reference in this prospectus supplement and the accompanying base prospectus and you should not consider it a part of this prospectus supplement and the accompanying base prospectus. These filings will be available as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC.

We have filed with the SEC a registration statement under the Securities Act relating to the offering of these securities. The registration statement, including the attached exhibits, contains additional relevant information about us and the securities. This prospectus supplement does not contain all of the information set forth in the registration statement. You can obtain a copy of the registration statement, at prescribed rates, from the SEC at the address listed above. The registration statement and the documents referred to above are also available free of charge on our corporate website at www.vikingtherapeutics.com. Unless specifically listed above, the information contained on the SEC website or our website is not incorporated by reference into this prospectus supplement and you should not consider that information a part of this prospectus supplement. You may obtain a copy of any of these documents at no cost, by writing or telephoning us at the following address:

Viking Therapeutics, Inc.
9920 Pacific Heights Blvd, Suite 500
San Diego, California 92121
Telephone: (858) 704-4660

This prospectus supplement may contain information that updates, modifies or is contrary to information in one or more of the documents incorporated by reference in this prospectus supplement. You should rely only on the information incorporated by reference or provided in this prospectus supplement. We have not authorized anyone else to provide you with different information. You should not assume that the information in this prospectus supplement is accurate as of any date other than the date of this prospectus supplement or the date of the documents incorporated by reference in this prospectus supplement.

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PROSPECTUS

Viking Therapeutics, Inc.

Common Stock

Preferred Stock

Debt Securities

Warrants

Rights

Units

Depositary Shares

We may offer and sell, from time to time in one or more offerings, any combination of the securities identified above, either individually or in combination with other securities. We may also offer common stock or preferred stock upon conversion of debt securities, common stock upon conversion of preferred stock, or common stock, preferred stock or debt securities upon the exercise of warrants, rights, units or depositary shares.

This prospectus provides a general description of the securities we may offer. Each time we offer and sell securities, we will provide a supplement to this prospectus that contains specific information about the offering and the amounts, prices and terms of the securities. We may also authorize one or more free writing prospectuses to be provided to you in connection with these offerings. The prospectus supplement and any related free writing prospectuses may also add, update or change information contained in this prospectus with respect to that offering. You should carefully read this prospectus and the applicable prospectus supplement and any related free writing prospectus, as well as any documents incorporated by reference herein or therein, before you invest in any of our securities.

We may offer and sell the securities described in this prospectus and any prospectus supplement to or through one or more underwriters, dealers and agents, or directly to purchasers, or through a combination of these methods. If any underwriters, dealers or agents are involved in the sale of any of the securities, their names and any applicable purchase price, fee, commission or discount arrangement between or among them will be set forth, or will be calculable from the information set forth, in the applicable prospectus supplement. See the sections of this prospectus entitled &#x201c;About this Prospectus&#x201d; and &#x201c;Plan of Distribution&#x201d; for more information. No securities may be sold without delivery of this prospectus and the applicable prospectus supplement describing the method and terms of the offering of such securities.

Investing in our securities involves a high degree of risk. You should review carefully the risks and uncertainties described under the heading &#x201c;Risk Factors&#x201d; on page 7 of this prospectus, the applicable prospectus supplement and in any applicable free writing prospectuses, and under similar headings in the documents that are incorporated by reference into this prospectus.

Our common stock is currently listed on the Nasdaq Capital Market under the symbol &#x201c;VKTX&#x201d;. On July 28, 2026, the last reported sales price for our common stock was $33.86 per share. The applicable prospectus supplement will contain information, where applicable, as to any other listing on the Nasdaq Capital Market or any securities market or other exchange of the securities, if any, covered by the applicable prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is July 29, 2026.

TABLE OF CONTENTS

Page

About this Prospectus

1

Disclosure Regarding Forward-Looking Statements

2

Summary

4

Risk Factors

7

Use of Proceeds

8

Description of Capital Stock

9

Description of Debt Securities

13

Description of Warrants

20

Description of Rights

22

Description of Units

23

Description of Depositary Shares

24

Legal Ownership of Securities

27

Plan of Distribution

30

Legal Matters

32

Experts

32

Where You Can Find More Information

32

Important Information Incorporated by Reference

33

ABOUT THIS PROSPECTUS

This prospectus is part of an &#x201c;automatic shelf&#x201d; registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or the SEC, as a &#x201c;well-known seasoned issuer&#x201d; as defined in Rule 405 under the Securities Act of 1933, as amended, or the Securities Act, utilizing a &#x201c;shelf&#x201d; registration process. Under this shelf registration process, we may offer and sell any combination of the securities described in this prospectus in one or more offerings. This prospectus provides you with a general description of the securities we may offer.

Each time we offer securities under this prospectus, we will provide a prospectus supplement that will contain more specific information about the terms of those securities and that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement and any related free writing prospectus we have authorized for use in connection with a specific offering may also add, update or change any of the information contained in this prospectus or in the documents that we have incorporated by reference into this prospectus. To the extent that any statement that we make in a prospectus supplement is inconsistent with statements made in this prospectus, the statements made in this prospectus will be deemed modified or superseded by those made in a prospectus supplement. We urge you to read carefully this prospectus, the applicable prospectus supplement and any free writing prospectuses we have authorized for use in connection with a specific offering, together with the information incorporated herein by reference as described under the section entitled &#x201c;Important Information Incorporated by Reference&#x201d;, before buying any of the securities being offered.

This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.

You should rely only on the information contained in, or incorporated by reference into, this prospectus, the applicable prospectus supplement and any free writing prospectuses, along with the information contained in any free writing prospectuses we have authorized for use in connection with a specific offering. We have not authorized anyone to provide you with different or additional information. This prospectus is an offer to sell only the securities offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so.

The information appearing in this prospectus, the applicable prospectus supplement or any related free writing prospectus is accurate only as of the date on the front of the document and any information we have incorporated by reference is accurate only as of the date of the document incorporated by reference, regardless of the time of delivery of this prospectus, the applicable prospectus supplement or any related free writing prospectus, or any sale of a security. Our business, financial condition, results of operations and prospects may have changed since those dates.

This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below under the heading &#x201c;Where You Can Find More Information&#x201d;.

For investors outside the United States: neither we nor any of our respective affiliates have done anything that would permit this offering or the possession or distribution of this prospectus in any jurisdiction where action for those purposes is required, other than in the United States. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, this offering of securities and the distribution of this prospectus outside the United States.

Unless the context otherwise requires, the terms &#x201c;Viking,&#x201d; &#x201c;the Company,&#x201d; &#x201c;we,&#x201d; &#x201c;us&#x201d; and &#x201c;our&#x201d; in this prospectus refer to Viking Therapeutics, Inc. and its consolidated subsidiary.

1

DISCLOSURE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, any accompanying prospectus supplement and the documents incorporated by reference in this prospectus contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act, which statements involve substantial risks and uncertainties. Forward-looking statements generally relate to future events or our future financial or operating performance. In some cases, you can identify forward-looking statements because they contain words such as &#x201c;may,&#x201d; &#x201c;will,&#x201d; &#x201c;should,&#x201d; &#x201c;expects,&#x201d; &#x201c;plans,&#x201d; &#x201c;anticipates,&#x201d; &#x201c;could,&#x201d; &#x201c;intends,&#x201d; &#x201c;target,&#x201d; &#x201c;projects,&#x201d; &#x201c;contemplates,&#x201d; &#x201c;believes,&#x201d; &#x201c;estimates,&#x201d; &#x201c;predicts,&#x201d; &#x201c;potential&#x201d; or &#x201c;continue&#x201d; or the negative of these words or other similar terms or expressions that concern our expectations, strategy, plans or intentions. Forward-looking statements contained in this prospectus and the documents incorporated by reference in this prospectus include, but are not limited to, statements about:

&#x2022;
risks and uncertainties associated with our research and development activities, including our clinical trials and preclinical studies, and the timing for commencing, completing and announcing results for such trials and studies;
&#x2022;
the timing or likelihood of regulatory filings and approvals or of alternative regulatory pathways for our product candidates;
&#x2022;
the potential market opportunities for commercializing our product candidates;
&#x2022;
our expectations regarding the potential market size and the size of the patient populations for our product candidates, if approved for commercial use, and our ability to serve such markets;
&#x2022;
estimates of our expenses, future revenue, capital requirements and our needs for additional financing;
&#x2022;
our ability to develop, acquire and advance our product candidates into, and successfully complete, clinical trials and preclinical studies, and obtain regulatory approvals;
&#x2022;
the implementation of our business model and strategic plans for our business and product candidates;
&#x2022;
the initiation, cost, timing, progress and results of future and current preclinical studies and clinical trials, and our research and development programs;
&#x2022;
new product candidates;
&#x2022;
the terms of future licensing arrangements, and whether we can enter into such arrangements at all;
&#x2022;
timing and receipt, or payments, of licensing and milestone revenues, if any;
&#x2022;
the scope of protection we are able to establish and maintain for intellectual property rights covering our product candidates, and our ability to operate our business without infringing the intellectual property rights of others;
&#x2022;
regulatory developments in the United States and foreign countries;
&#x2022;
the performance of our third-party suppliers and manufacturers;
&#x2022;
our ability to maintain and establish collaborations or obtain additional funding;
&#x2022;
the success of competing therapies that are currently or may become available;
&#x2022;
our use of proceeds from the sale of securities under this prospectus;
&#x2022;
our financial performance; and
&#x2022;
developments and projections relating to our competitors and our industry.

We caution you that the forward-looking statements highlighted above do not encompass all of the forward-looking statements made in this prospectus or in the documents incorporated by reference in this prospectus.

2

We have based the forward-looking statements contained in this prospectus, the applicable prospectus supplement and any related free-writing prospectus and in the documents incorporated by reference in this prospectus primarily on our current expectations and projections about future events and trends that we believe may affect our business, financial condition, results of operations and prospects. The outcomes of the events described in these forward-looking statements are subject to risks, uncertainties and other factors that could cause actual results and experience to differ from those projected, including, but not limited to, the risk factors set forth in Part I - Item 1A, &#x201c;Risk Factors&#x201d;, in our Annual Report on Form 10-K for the year ended December 31, 2025, as filed with the SEC on February 11, 2026, in our Quarterly Report on Form 10-Q for the quarter ended March 31, 2026, as filed with the SEC on April 30, 2026, in our Quarterly Report on Form 10-Q for the quarter ended June 30, 2026, as filed with the SEC on July 29, 2026, and elsewhere in the documents incorporated by reference into this prospectus. Moreover, we operate in a very competitive and challenging environment. New risks and uncertainties emerge from time to time, and it is not possible for us to predict all risks and uncertainties that could have an impact on the forward-looking statements contained in this prospectus, the applicable prospectus supplement and any related free-writing prospectus and in the documents incorporated by reference in this prospectus. We cannot assure you that the results, events and circumstances reflected in the forward-looking statements will be achieved or occur, and actual results, events or circumstances could differ materially from those described in the forward-looking statements.

The forward-looking statements contained in this prospectus, the applicable prospectus supplement and any related free-writing prospectus and in the documents incorporated by reference in this prospectus relate only to events as of the date on which the statements are made. We do not undertake any obligation to release publicly any revisions to such forward-looking statements to reflect events or circumstances after the date of this prospectus or to reflect the occurrence of unanticipated events. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, joint ventures, other strategic transactions or investments we may make.

3

SUMMARY

This summary highlights selected information that is presented in greater detail elsewhere in this prospectus or incorporated by reference in this prospectus. Because it is only a summary, it does not contain all of the information you should consider before investing in our common stock, preferred stock, debt securities, warrants, rights, units or depositary shares, and it is qualified in its entirety by, and should be read in conjunction with, the more detailed information included elsewhere in this prospectus. Before you decide whether to purchase shares of our common stock or preferred stock, or our debt securities, warrants, rights, units or depositary shares, you should read this entire prospectus, the applicable prospectus supplement and any related free-writing prospectus carefully, including the risks of investing in our securities discussed under the heading &#x201c;Risk Factors&#x201d; contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. You should also carefully read the information incorporated by reference into this prospectus, including our consolidated financial statements, and the exhibits to the registration statement of which this prospectus is a part.

The Company

We are a clinical-stage biopharmaceutical company focused on the development of novel, first-in-class or best-in-class therapies for metabolic and endocrine disorders.

In January 2022, we announced the initiation of a Phase 1 single ascending dose, or SAD, and multiple ascending dose, or MAD, clinical trial of VK2735, a novel dual agonist of the glucagon-like peptide 1, or GLP-1, and glucose-dependent insulinotropic polypeptide, or GIP, receptors. VK2735 is being developed in both oral and subcutaneous formulations for the potential treatment of various metabolic disorders such as obesity.

In March 2023, we announced the completion of the Phase 1 trial. The study was a randomized, double-blind, placebo-controlled, SAD and MAD study in healthy adults. The primary objectives of the study included evaluation of the safety and tolerability of single and multiple doses of VK2735 delivered subcutaneously and the identification of VK2735 doses suitable for further clinical development. Study investigators also evaluated the pharmacokinetics of single and multiple doses of VK2735. Based upon the results from this Phase 1 study, in September 2023, we initiated the VENTURE study, a Phase 2 clinical trial of VK2735 in patients with obesity.

The Phase 2 VENTURE study was a randomized, double-blind placebo-controlled study to evaluate the safety, tolerability, pharmacokinetics and weight loss efficacy of VK2735, administered subcutaneously, once weekly. The 13-week study enrolled adults who were obese (BMI >= 30 kg/m2) or adults who were overweight (BMI >= 27 kg/m2) with at least one weight-related co-morbidity condition. The primary endpoint of the study was the percent change in body weight from baseline to week 13, with secondary and exploratory endpoints evaluating a range of additional safety and efficacy measures. In October 2023, we announced completion of patient enrollment in the Phase 2 VENTURE study and on February 27, 2024, we announced that patients receiving weekly doses of VK2735 demonstrated statistically significant reductions in mean body weight after 13 weeks, ranging up to 14.7% from baseline. Patients receiving VK2735 also demonstrated statistically significant reductions in mean body weight relative to placebo, ranging up to 13.1%. VK2735 demonstrated encouraging safety and tolerability following 13 weeks of once-weekly dosing.

In June 2025, we announced the initiation of two Phase 3 clinical studies to evaluate the subcutaneous formulation of VK2735, VANQUISH-1 and VANQUISH-2. In November 2025, we announced completion of patient enrollment in the VANQUISH-1 study. In March 2026, we announced the completion of patient enrollment in the VANQUISH-2 study.

In March 2023, we announced the initiation of a Phase 1 clinical study to evaluate a novel oral formulation of VK2735. The study, which was an extension of our completed Phase 1 evaluation of subcutaneously administered VK2735, evaluated daily oral doses for 28 days. In March 2024, we announced that the 28-day MAD study results highlighted positive signs of clinical activity following treatment with oral VK2735. Cohorts receiving VK2735 demonstrated dose-dependent reductions in mean body weight from baseline, ranging up to approximately 5.3%. Oral VK2735 demonstrated encouraging safety and tolerability following 28 days of once-daily dosing.

In January 2025, we announced the initiation of a Phase 2 clinical trial of the oral tablet formulation of VK2735, and in August 2025, we announced positive top-line results from the trial. The Phase 2 VENTURE-Oral Dosing trial successfully achieved its primary and secondary endpoints, with patients receiving oral VK2735 demonstrating statistically significant reductions in body weight compared with placebo, ranging up to 12.2% from baseline. Additionally, the trial showed oral VK2735 treatment to be safe and well-tolerated through 13 weeks of daily dosing with the majority of treatment emergent adverse events being categorized as mild or moderate. We expect to initiate Phase 3 oral dosing studies in the fourth quarter of 2026.

In October 2025, we announced the initiation of an exploratory maintenance dosing study of VK2735. This study is intended to explore the feasibility of various VK2735 maintenance dosing regimens utilizing either the oral tablet or the subcutaneous formulation

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to sustain the initial weight loss achieved following subcutaneous dosing. In January 2026, we announced completion of enrollment in this study.

In March 2025, we entered into broad, multi-year manufacturing agreements, or the Manufacturing Agreements, with Corden Pharma Colorado, Inc. and its affiliates, or CordenPharma, covering both the active pharmaceutical ingredient, or API, and final finished product supply for VK2735.

Under the terms of the Manufacturing Agreements, we have secured dedicated capacity for the annual manufacture and supply of multiple metric tons of VK2735 API. In addition, CordenPharma will provide fill/finish capacity for both the injectable and oral formulations of VK2735. This includes dedicated manufacturing lines and an annual commitment to supply 100 million autoinjectors and an additional 100 million vial and syringe products for the subcutaneous formulation, as well as an annual capacity of over one billion oral VK2735 tablets. These API and final finished product capacities are further expandable at our option. In exchange for dedicated API and fill/finish capacity, we will make prepayments to CordenPharma, to be paid over the period from 2026 to 2028. These prepayments will be fully credited against future orders.

In 2024, we announced a new, internally developed Dual Amylin and Calcitonin Receptor Agonist, or DACRA, program for the treatment of obesity and highlighted the effects of treatment on body weight, food intake and metabolic profile in both healthy rats and in diet-induced obese mice. The results demonstrated that our DACRAs reduced food intake in lean rats in the period from 0 &#x2013; 72 hours following a single subcutaneous dose. In April 2026, we announced that we filed an IND application for our Novel Amylin Agonist VK3019. In June 2026, we announced the initiation of a Phase 1 SAD clinical trial evaluating VK3019.

We are also developing VK2809, which is an orally available, tissue and receptor-subtype selective agonist of the thyroid hormone receptor beta, or TR&szlig;. In November 2019, we initiated the VOYAGE study, a Phase 2b clinical trial of VK2809 in patients with biopsy-confirmed non-alcoholic steatohepatitis, or NASH/MASH.

The VOYAGE study was a randomized, double-blind, placebo-controlled, multicenter trial designed to assess the efficacy, safety and tolerability of VK2809 in patients with biopsy-confirmed NASH/MASH and fibrosis ranging from stages F1 to F3. The primary endpoint of the study evaluated the relative change in liver fat content, as assessed by magnetic resonance imaging, proton density fat fraction, or MRI-PDFF, from baseline to week 12 in subjects treated with VK2809 as compared to placebo. Secondary objectives included evaluation of histologic changes assessed by hepatic biopsy after 52 weeks of dosing.

In January 2023, we announced completion of patient enrollment in the VOYAGE study and in May 2023 we reported that the VOYAGE study successfully achieved its primary endpoint, with patients receiving VK2809 experiencing statistically significant reductions in liver fat content from baseline to Week 12 as compared to placebo.

In June 2024, we announced positive 52-week histologic data from the VOYAGE study with up to 75% of patients treated with VK2809 achieving NASH/MASH resolution with no worsening of fibrosis as compared to 29% for placebo (p=0.0001), up to 57% of VK2809-treated patients achieving &#x2265;1-stage improvement in fibrosis with no worsening of NASH/MASH as compared to 34% for placebo (p<0.05) and up to 48% of VK2809-treated patients achieving both resolution of NASH/MASH and a &#x2265;1-stage improvement in fibrosis as compared to 20% for placebo (p=0.01). Adverse events, including gastrointestinal-related adverse events, were similar among VK2809-treated patients vs. placebo at week 52 and consistent with prior data reported at week 12. VK2809 has been evaluated in eight completed clinical studies, which enrolled more than 400 subjects.

We are also developing VK0214, which is also an orally available, tissue and receptor-subtype selective agonist of TR&szlig; for X-linked adrenoleukodystrophy, or X-ALD, a rare X-linked, inherited neurological disorder characterized by a breakdown in the protective barriers surrounding brain and nerve cells. The disease, for which there is no approved treatment, is caused by mutations in a peroxisomal transporter of very long chain fatty acids, or VLCFA, known as ABCD1. As a result, transporter function is impaired and patients are unable to efficiently metabolize VLCFA. The TR&szlig; receptor is known to regulate expression of an alternative VLCFA transporter, known as ABCD2. Various preclinical models have demonstrated that increased expression of ABCD2 can lead to normalization of VLCFA metabolism. Preliminary data suggest that VK0214 stimulates ABCD2 expression in an in vitro model and reduces VLCFA levels in an in vivo model of X-ALD.

In June 2021, we initiated a Phase 1b clinical trial of VK0214 in patients with X-ALD. This trial was a multi-center, randomized, double-blind, placebo-controlled study in adult male patients with the adrenomyeloneuropathy, or AMN, form of X-ALD. The study enrolled patients across three cohorts: placebo, VK0214 20 mg daily, and VK0214 40 mg daily.

The primary objectives of the study were to evaluate the safety and tolerability of VK0214 administered once-daily over a 28-day dosing period. Secondary objectives included an evaluation of the pharmacokinetics of VK0214 following 28 days of dosing in this population. An exploratory objective was to evaluate the effects of VK0214 on plasma levels of VLCFAs in subjects with AMN. In October 2024, we announced results from the Phase 1b clinical trial, which showed VK0214 to be safe and well-tolerated following

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once-daily dosing over the 28-day study period. In addition, significant reductions were observed in plasma levels of VLCFAs and other lipids, as compared to placebo. Our intent is to pursue partnering or licensing opportunities for VK0214 prior to conducting additional clinical studies.

Other programs include VK5211, an orally available, non-steroidal selective androgen receptor modulator. In November 2017, we announced positive top-line results from a Phase 2 proof-of-concept clinical trial in 108 patients recovering from non-elective hip fracture surgery. Top-line data showed that the trial achieved its primary endpoint, demonstrating statistically significant, dose-dependent increases in total lean body mass, less head, following treatment with VK5211 as compared to placebo. The study also achieved certain secondary endpoints, demonstrating statistically significant increases in appendicular lean body mass and total lean body mass for all doses of VK5211, compared to placebo. VK5211 demonstrated encouraging safety and tolerability in this study, with no drug-related serious adverse events reported. Our intent is to continue to pursue partnering or licensing opportunities for VK5211 prior to conducting additional clinical studies.

We were incorporated under the laws of the State of Delaware on September 24, 2012. Since our incorporation, we have devoted most of our efforts towards conducting certain clinical trials and preclinical studies related to our VK2735 subcutaneous, VK2735 oral, VK3019, VK2809, VK0214 and VK5211 programs and towards raising capital and building infrastructure. We obtained exclusive worldwide rights to VK2809, VK0214 and VK5211 and certain other assets pursuant to an exclusive license agreement with Ligand Pharmaceuticals Incorporated, or Ligand. The terms of this license agreement are detailed in a Master License Agreement with Ligand, which we entered into on May 21, 2014, as amended, or the Master License Agreement. A summary of the Master License Agreement can be found under the heading &#x201c;Agreements with Ligand&#x2014;Master License Agreement&#x201d; under Part I, &#x201c;Item 1. Business&#x201d; of our Annual Report on Form 10-K filed with the SEC on February 11, 2026.

Corporate Information

For a complete description of our business, financial condition, results of operations and other important information, we refer you to our filings with the SEC that are incorporated by reference in this prospectus, including our Annual Report on Form 10-K for the year ended December 31, 2025, as filed with the SEC on February 11, 2026, our Quarterly Report on Form 10-Q for the quarter ended March 31, 2026, as filed with the SEC on April 30, 2026, and our Quarterly Report on Form 10-Q for the quarter ended June 30, 2026, as filed with the SEC on July 29, 2026. For instructions on how to find copies of these documents, see the section of this prospectus entitled &#x201c;Where You Can Find More Information.&#x201d;

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RISK FACTORS

Investing in any securities offered pursuant to this prospectus, the applicable prospectus supplement and any related free writing prospectus involves a high degree of risk. Before making an investment decision, you should carefully consider the risks described under &#x201c;Risk Factors&#x201d; in the applicable prospectus supplement, any related free writing prospectus and in our most recent Annual Report on Form 10-K, or any updates in our Quarterly Reports on Form 10-Q, together with all of the other information appearing in or incorporated by reference into this prospectus, the applicable prospectus supplement and any related free writing prospectus, before deciding whether to purchase any of the securities being offered. Our business, financial condition or results of operations could be materially adversely affected by any of these risks. The occurrence of any of these risks might cause you to lose all or part of your investment in the offered securities.

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USE OF PROCEEDS

Except as described in the applicable prospectus supplement or in any free-writing prospectuses we have authorized for use in connection with a specific offering, we currently intend to use the net proceeds from the sale of securities under this prospectus, if any, for working capital and general corporate purposes, which may include, without limitation, supporting asset growth and engaging in acquisitions or other business combinations.

The amounts and timing of our use of the net proceeds from the sale of securities under this prospectus will depend on a number of factors, such as the timing and progress of our research and development efforts, the timing and progress of any partnering and commercialization efforts, technological advances and the competitive environment for our products. As of the date of this prospectus, we cannot specify with certainty all of the particular uses for the net proceeds to us from the sale of securities under this prospectus or any applicable prospectus supplement. Accordingly, our management will have broad discretion in the timing and application of these proceeds. Pending application of the net proceeds as described above, we intend to temporarily invest the proceeds in interest-bearing instruments.

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DESCRIPTION OF CAPITAL STOCK

General

The following description summarizes the most important terms of our capital stock. Because it is only a summary of the provisions of our amended and restated certificate of incorporation and amended and restated bylaws, it does not contain all of the information that may be important to you. For a complete description of the matters set forth in this &#x201c;Description of Capital Stock&#x201d;, you should refer to our amended and restated certificate of incorporation and amended and restated bylaws, each of which is included as an exhibit to the registration statement of which this prospectus is a part, and to the applicable provisions of Delaware law. Our authorized capital stock consists of 300,000,000 shares of common stock, $0.00001 par value per share, and 10,000,000 shares of undesignated preferred stock, $0.00001 par value per share.

As of June 30, 2026, there were 116,652,937 shares of our common stock outstanding. Our board of directors is authorized, without stockholder approval except as required by the rules and listing standards of The Nasdaq Stock Market LLC, to issue additional shares of our capital stock.

Common Stock

Dividend Rights

Subject to preferences that may apply to any shares of preferred stock outstanding at the time, the holders of our common stock are entitled to receive dividends out of funds legally available if our board of directors, at its discretion, determines to issue dividends and then only at the times and in the amounts that our board of directors may determine.

Voting Rights

Holders of our common stock are entitled to one vote for each share held on all matters submitted to a vote of stockholders. Our amended and restated certificate of incorporation does not provide for cumulative voting for the election of directors, and it establishes a classified board of directors that is divided into three classes with staggered three-year terms. Only the directors in one class will be subject to election at each annual meeting of our stockholders with the directors in the other classes continuing for the remainder of their respective three-year terms.

No Preemptive or Similar Rights

Holders of our common stock are not entitled to preemptive rights, and our common stock is not subject to conversion, redemption or sinking fund provisions.

Right to Receive Liquidation Distributions

If we become subject to a liquidation, dissolution or winding-up, the assets legally available for distribution to our stockholders would be distributable ratably among the holders of our common stock and any participating preferred stock outstanding at that time, subject to prior satisfaction of all outstanding debt and liabilities and the preferential rights of and the payment of liquidation preferences, if any, on any outstanding shares of preferred stock.

Fully Paid and Non-Assessable

All of the outstanding shares of our common stock are, and the shares of our common stock to be issued pursuant to this prospectus or which may be issued upon conversion of or exchange for preferred stock or debt securities that provide for conversion or exchange, or upon exercise of warrants, units or rights to be issued pursuant to this prospectus, will be, fully paid and non-assessable.

Preferred Stock

Our board of directors is authorized, subject to limitations prescribed by Delaware law, to issue up to 10,000,000 shares of our preferred stock in one or more series, to establish from time to time the number of shares to be included in each series, and to fix the designation, powers, preferences, and rights of the shares of each series and any of its qualifications, limitations or restrictions, in each case without further vote or action by our stockholders. Our board of directors can also increase or decrease the number of shares of any series of preferred stock, but not below the number of shares of that series then outstanding, without any further vote or action by our stockholders. Our board of directors may authorize the issuance of preferred stock with voting or conversion rights that could adversely affect the voting power or other rights of the holders of our common stock. The issuance of preferred stock, while providing flexibility in connection with possible acquisitions and other corporate purposes, could, among other things, have the effect of delaying, deferring or preventing a change in control of our company and might adversely affect the market price of our common stock and the voting and other rights of the holders of our common stock.

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Equity Awards

As of June 30, 2026, options to purchase 5,990,015 shares of our common stock with a weighted-average exercise price of $17.83 per share were outstanding; restricted stock awards representing an aggregate of 30,211 shares of our common stock were unvested and outstanding; and restricted stock units representing 1,813,501 shares of our common stock were outstanding.

Anti-Takeover Provisions

Certain provisions of Delaware law, along with certain provisions of our amended and restated certificate of incorporation and our amended and restated bylaws, may have the effect of delaying, deferring or discouraging another person from acquiring control of our company. These provisions are expected to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed, in part, to encourage persons seeking to acquire control of our company to first negotiate with our board of directors. However, these provisions could have the effect of delaying, discouraging or preventing attempts to acquire us, which could deprive our stockholders of opportunities to sell their shares of common stock at prices higher than prevailing market prices.

Delaware Law

We are subject to the provisions of Section 203 of the General Corporation Law of the State of Delaware, or the DGCL, regulating corporate takeovers. In general, those provisions prohibit a public Delaware corporation from engaging in any business combination with any interested stockholder for a period of three years following the date that the stockholder became an interested stockholder, unless:

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the transaction is approved by the board of directors before the date the interested stockholder attained that status;
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upon consummation of the transaction which resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced; or
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on or after the date of the transaction, the transaction is approved by the board of directors and authorized at a meeting of stockholders, and not by written consent, by the affirmative vote of at least 66 2/3% of the outstanding voting stock that is not owned by the interested stockholder.


In general, Section 203 of the DGCL defines a business combination to include the following:

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any merger or consolidation involving the corporation and the interested stockholder;
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any sale, transfer, pledge or other disposition of 10% or more of the assets of the corporation involving the interested stockholder;
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subject to certain exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder;
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any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder; or
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the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.

In general, Section 203 of the DGCL defines an interested stockholder as any entity or person beneficially owning, or who within three years prior to the time of determination of interested stockholder status did own, 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by any such entity or person.

A Delaware corporation may opt out of this provision by express provision in its original certificate of incorporation or by amendment to its certificate of incorporation or bylaws approved by its stockholders. However, we have not opted out of, and do not currently intend to opt out of, this provision. The statute could prohibit or delay mergers or other takeover or change in control attempts and, accordingly, may discourage attempts to acquire our company.

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Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws

Our amended and restated certificate of incorporation and our amended and restated bylaws include a number of provisions that could deter hostile takeovers or delay or prevent changes relating to the control of our board of directors or management team, including the following:

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Board of Directors Vacancies. Our amended and restated certificate of incorporation and amended and restated bylaws authorize only our board of directors to fill vacant directorships, including newly created seats. In addition, the number of directors constituting our board of directors can be set only by a resolution adopted by a majority vote of our entire board of directors. These provisions would prevent a stockholder from increasing the size of our board of directors and then gaining control of our board of directors by filling the resulting vacancies with its own nominees. This makes it more difficult to change the composition of our board of directors and promotes continuity of management.
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Classified Board. Our amended and restated certificate of incorporation and amended and restated bylaws provide that our board of directors is classified into three classes of directors. A third party may be discouraged from making a tender offer or otherwise attempting to obtain control of our company as it is more difficult and time consuming for stockholders to replace a majority of the directors on a classified board of directors.
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Stockholder Action; Special Meeting of Stockholders. Our amended and restated certificate of incorporation provides that our stockholders may not take action by written consent, but may only take action at annual or special meetings of our stockholders. As a result, a holder controlling a majority of our capital stock would not be able to amend our amended and restated bylaws or remove directors without holding a meeting of our stockholders called in accordance with our amended and restated bylaws. Our amended and restated bylaws further provide that special meetings of our stockholders may be called only by a majority of our board of directors, the Chairperson of our board of directors, our Chief Executive Officer or our President, thus prohibiting a stockholder (in the capacity as a stockholder) from calling a special meeting. These provisions might delay the ability of our stockholders to force consideration of a proposal or for stockholders controlling a majority of our capital stock to take any action, including the removal of directors.
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Advance Notice Requirements for Stockholder Proposals and Director Nominations. Our amended and restated bylaws provide advance notice procedures for stockholders seeking to bring business before our annual meeting of stockholders or to nominate candidates for election as directors at our annual meeting of stockholders. Our amended and restated bylaws also specify certain requirements regarding the form and content of a stockholder&#x2019;s notice. These provisions might preclude our stockholders from bringing matters before our annual meeting of stockholders or from making nominations for directors at our annual meeting of stockholders if the proper procedures are not followed. We expect that these provisions may also discourage or deter a potential acquirer from conducting a solicitation of proxies to elect the acquirer&#x2019;s own slate of directors or otherwise attempting to obtain control of our company.
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No Cumulative Voting. The DGCL provides that stockholders may cumulate votes in the election of directors if the corporation&#x2019;s certificate of incorporation allows for such mechanism. Our amended and restated certificate of incorporation does not provide for cumulative voting.
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Directors Removed Only for Cause. Our amended and restated certificate of incorporation provides that stockholders may remove directors only for cause.
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Choice of Forum. Our amended and restated bylaws provide that, unless we consent in writing to the selection of an alternative forum, the Court of Chancery in the State of Delaware, or the Court of Chancery, shall be the sole and exclusive forum for any stockholder (including a beneficial owner) to bring (a) any derivative action or proceeding on behalf of us, (b) any action asserting a claim of breach of fiduciary duty owed by any director, officer or other employee of the Company to us or our stockholders, (c) any action asserting a claim against us, our directors, officers or employees arising pursuant to our amended and restated bylaws, our amended and restated certificate of incorporation or the DGCL, (d) any action asserting a claim against us or our directors, officers or employees governed by the internal affairs doctrine, or (e) any action to interpret, apply, enforce or determine the validity of our amended and restated bylaws or our amended and restated certificate of incorporation, except for, as to each of clauses (a) through (e), any claim (i) as to which the Court of Chancery determines that there is an indispensable party not subject to the jurisdiction of the Court of Chancery (and the indispensable party does not consent to the personal jurisdiction of the Court of Chancery within 10 days following such determination), or (ii) for which the Court of Chancery does not have subject matter jurisdiction. This exclusive forum provision is not intended to apply to any actions brought under the Securities Act or the Exchange Act. Section 27 of the Exchange Act creates exclusive federal jurisdiction over all suits brought to enforce any duty or liability created by the Exchange Act or the rules and regulations thereunder. As a result, the exclusive forum provision will not apply to suits brought to enforce any duty or liability created by the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction. However, our amended and restated bylaws do not relieve us of our duty to comply with federal securities laws and the rules and regulations thereunder, and our stockholders will not be deemed to have waived our compliance with these laws, rules and

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regulations. This exclusive forum provision in our amended and restated bylaws may limit a stockholder&#x2019;s ability to bring a claim in a judicial forum that it finds favorable for disputes with us or our directors, officers or other employees, which may discourage such lawsuits against us and our directors, officers and other employees. In addition, stockholders who do bring a claim in the Court of Chancery in the State of Delaware could face additional litigation costs in pursuing any such claim, particularly if they do not reside in or near Delaware. Furthermore, the enforceability of similar choice of forum provisions in other companies&#x2019; governing documents has been challenged in legal proceedings, and it is possible that a court could find these types of provisions to be inapplicable or unenforceable.
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Amendment of Charter Provisions. Any amendment of the above provisions in our amended and restated certificate of incorporation, with the exception of the ability of our board of directors to issue shares of preferred stock and designate any rights, preferences and privileges thereto, would require approval by the affirmative vote of the holders of at least 66 2/3% of our then outstanding common stock.
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Issuance of Undesignated Preferred Stock. Our board of directors has the authority, without further action by the stockholders, to issue up to 10,000,000 shares of undesignated preferred stock with rights and preferences, including voting rights, designated from time to time by our board of directors. The existence of authorized but unissued shares of preferred stock would enable our board of directors to render more difficult or to discourage an attempt to obtain control of our company by means of a merger, tender offer, proxy contest or other means.

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Equiniti Trust Company, LLC. The transfer agent and registrar&#x2019;s address is 1110 Centre Pointe Curve, Suite 101, Mendota Heights, MN 55120.

Listing

Our common stock is listed on the Nasdaq Capital Market under the symbol &#x201c;VKTX&#x201d;.

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DESCRIPTION OF DEBT SECURITIES

This prospectus describes the general terms and provisions of our debt securities. When we offer to sell a particular series of debt securities, we will describe the specific terms of the series in a supplement to this prospectus. We will also indicate in the prospectus supplement whether the general terms and provisions described in this prospectus apply to a particular series of debt securities. To the extent the information contained in the prospectus supplement differs from this summary description, you should rely on the information in the prospectus supplement.

Unless otherwise specified in a supplement to this prospectus, the debt securities will be our direct, unsecured obligations and will rank equally with all of our other unsecured and unsubordinated indebtedness. In the event that any series of debt securities will be subordinated to other indebtedness that we have outstanding or may incur, the terms of the subordination will be set forth in the prospectus supplement relating to the subordinated debt securities.

The debt securities will be issued under an indenture between Viking and a trustee named in the prospectus supplement. We have summarized select portions of the indenture below. The summary is not complete. The form of the indenture has been filed as an exhibit to the registration statement and you should read the indenture for provisions that may be important to you. Capitalized terms used in the summary have the meaning specified in the indenture.

General

The terms of each series of debt securities will be established by or pursuant to a resolution of our board of directors and set forth or determined in the manner provided in a resolution of our board of directors, in an officer&#x2019;s certificate or by a supplemental indenture. The particular terms of each series of debt securities will be described in a prospectus supplement relating to such series, including any pricing supplement or term sheet.

We can issue an unlimited amount of debt securities under the indenture that may be in one or more series with the same or various maturities, at par, at a premium, or at a discount. We will set forth in a prospectus supplement, including any pricing supplement or term sheet, relating to any series of debt securities being offered, the aggregate principal amount and the following terms of the debt securities, to the extent applicable:

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the title of the debt securities;
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the price or prices (expressed as a percentage of the principal amount) at which we will issue the debt securities;
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any limit on the aggregate principal amount of the debt securities;
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the date or dates on which we will pay the principal on the debt securities;
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the form of the debt securities;
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the rate or rates (which may be fixed or variable) per annum or the method used to determine the rate or rates (including any commodity, commodity index, stock exchange index or financial index) at which the debt securities will bear interest, the date or dates from which interest will accrue, the date or dates on which interest will commence and be payable and any regular record date for the interest payable on any interest payment date;
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the place or places where principal of and interest on the debt securities will be payable;
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the applicability of any guarantees;
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the terms and conditions upon which we may redeem the debt securities;
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whether and under what circumstances, if any, we will pay additional amounts on any debt securities held by a person who is not a United States person for tax purposes, and whether we can redeem the debt securities if we have to pay such additional amounts;
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any obligation we have to redeem or purchase the debt securities pursuant to any sinking fund or analogous provisions or at the option of a holder of debt securities;
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the dates on which and the price or prices at which we will repurchase debt securities at the option of the holders of debt securities and other detailed terms and provisions of these repurchase obligations;
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the denominations in which the debt securities will be issued, if other than denominations of $1,000 and any integral multiple thereof;
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whether the debt securities will be issued in the form of certificated debt securities or global debt securities;
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if the debt securities of the series will be issued in whole or in part in the form of a global debt security, the terms and conditions, if any, upon which such global debt security may be exchanged in whole or in part for other individual debt securities in definitive registered form, the depositary (as defined in the applicable prospectus supplement) for such global

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debt security and the form of any legend or legends to be borne by any such global debt security in addition to or in lieu of the legend referred to in the indenture;
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the principal amount due at maturity, and whether the debt securities will be issued with original issue discount;
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the portion of principal amount of the debt securities payable upon declaration of acceleration of the maturity date, if other than the principal amount;
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the currency of denomination of the debt securities;
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the designation of the currency, currencies or currency units in which payment of principal of and interest on the debt securities will be made;
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if payments of principal of or interest on the debt securities will be made in one or more currencies or currency units other than that or those in which the debt securities are denominated, the manner in which the exchange rate with respect to these payments will be determined;
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the manner in which the amounts of payment of principal of or interest on the debt securities will be determined, if these amounts may be determined by reference to an index based on a currency or currencies other than that in which the debt securities are denominated or designated to be payable or by reference to a commodity, commodity index, stock exchange index or financial index;
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any provisions relating to any security provided for the debt securities;
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the terms of the subordination of any series of the debt securities;
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restrictions on transfer, sale or other assignment of the debt securities, if any;
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if the principal amount payable at the stated maturity of debt securities of the series will not be determinable as of any one or more dates prior to such stated maturity, the amount that will be deemed to be such principal amount as of any such date for any purpose, including the principal amount thereof which will be due and payable upon any maturity other than the stated maturity or which will be deemed to be outstanding as of any such date (or, in any such case, the manner in which such deemed principal amount is to be determined), and if necessary, the manner of determining the equivalent thereof in U.S. dollars;
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the right, if any, to extend the interest payment periods or defer the payment of interest and maximum length of any such deferral period;
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with regard to the debt securities that do not bear interest, the dates for certain required reports to the trustee;
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any provisions granting special rights to holders when a specified event occurs;
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any addition to or change in the provisions relating to or dealing with defeasance;
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any addition to or change in the events of default described in this prospectus or in the indenture with respect to the debt securities and any change in the acceleration provisions described in this prospectus or in the indenture with respect to the debt securities;
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any addition to or change in the covenants described in this prospectus or in the indenture with respect to the debt securities;
&#x2022;
any other terms of the debt securities, which may supplement, modify or delete any provision of the indenture as it applies to that series; and
&#x2022;
any depositaries, interest rate calculation agents, exchange rate calculation agents or other agents with respect to the debt securities.

In addition, the indenture does not limit our ability to issue convertible or subordinated debt securities. Any conversion or subordination provisions of a particular series of debt securities will be set forth in the resolution of our board of directors, the officer&#x2019;s certificate or supplemental indenture related to that series of debt securities and will be described in the relevant prospectus supplement. Such terms may include provisions for conversion, either mandatory, at the option of the holder or at our option, in which case the number of shares of common stock or other securities to be received by the holders of debt securities would be calculated as of a time and in the manner stated in the prospectus supplement.

14

We may issue debt securities that provide for an amount less than their stated principal amount to be due and payable upon declaration of acceleration of their maturity pursuant to the terms of the indenture. We will provide you with information on the federal income tax considerations and other special considerations applicable to any of these debt securities in the applicable prospectus supplement.

If we denominate the purchase price of any of the debt securities in a foreign currency or currencies or a foreign currency unit or units, or if the principal of and interest on any series of debt securities is payable in a foreign currency or currencies or a foreign currency unit or units, we will provide you with information on the restrictions, elections, general tax considerations, specific terms and other information with respect to that issue of debt securities and such foreign currency or currencies or foreign currency unit or units in the applicable prospectus supplement.

Transfer and Exchange

Each debt security will be represented by either one or more global debt securities registered in the name of The Depository Trust Company, as depositary, or a nominee (we will refer to any debt security represented by a global debt security as a book-entry debt security), or a certificate issued in definitive registered form (we will refer to any debt security represented by a certificate as a certificated debt security) as set forth in the applicable prospectus supplement. Except as set forth under the heading &#x201c;&#x2014;Global Debt Securities and Book-Entry System&#x201d; below, book-entry debt securities will not be issuable in certificated form.

Certificated Debt Securities. You may transfer or exchange certificated debt securities at any office we maintain for this purpose in accordance with the terms of the indenture. No service charge will be made for any transfer or exchange of certificated debt securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with a transfer or exchange.

You may effect the transfer of certificated debt securities and the right to receive the principal of and interest on certificated debt securities only by surrendering the certificate representing those certificated debt securities and either reissuance by us or the trustee of the certificate to the new holder or the issuance by us or the trustee of a new certificate to the new holder.

Global Debt Securities and Book-Entry System. Each global debt security representing book-entry debt securities will be deposited with, or on behalf of, the depositary, and registered in the name of the depositary or a nominee of the depositary.

We will require the depositary to agree to follow the following procedures with respect to book-entry debt securities.

Ownership of beneficial interests in book-entry debt securities will be limited to persons who have accounts with the depositary for the related global debt security, which we refer to as participants, or persons who may hold interests through participants. Upon the issuance of a global debt security, the depositary will credit, on its book-entry registration and transfer system, the participants&#x2019; accounts with the respective principal amounts of the book-entry debt securities represented by such global debt security beneficially owned by such participants. The accounts to be credited will be designated by any dealers, underwriters or agents participating in the distribution of the book-entry debt securities. Ownership of book-entry debt securities will be shown on, and the transfer of such ownership interests will be effected only through, records maintained by the depositary for the related global debt security (with respect to interests of participants) and on the records of participants (with respect to interests of persons holding through participants). The laws of some states may require that certain purchasers of securities take physical delivery of such securities in definitive form. These laws may impair the ability to own, transfer or pledge beneficial interests in book-entry debt securities.

So long as the depositary for a global debt security, or its nominee, is the registered owner of that global debt security, the depositary or its nominee, as the case may be, will be considered the sole owner or holder of the book-entry debt securities represented by such global debt security for all purposes under the indenture. Except as described below, beneficial owners of book-entry debt securities will not be entitled to have securities registered in their names, will not receive or be entitled to receive physical delivery of a certificate in definitive form representing securities and will not be considered the owners or holders of those securities under the indenture. Accordingly, each person beneficially owning book-entry debt securities must rely on the procedures of the depositary for the related global debt security and, if such person is not a participant, on the procedures of the participant through which such person owns its interest, to exercise any rights of a holder under the indenture.

We understand, however, that under existing industry practice, the depositary will authorize the persons on whose behalf it holds a global debt security to exercise certain rights of holders of debt securities, and the indenture provides that we, the trustee and our respective agents will treat as the holder of a debt security the persons specified in a written statement of the depositary with respect to that global debt security for purposes of obtaining any consents or directions required to be given by holders of the debt securities pursuant to the indenture.

We will make payments of principal of, and premium and interest on, book-entry debt securities to the depositary or its nominee, as the case may be, as the registered holder of the related global debt security. Viking, the trustee and any other agent of ours or agent of the trustee will not have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in a global debt security or for maintaining, supervising or reviewing any records relating to beneficial ownership interests.

15

We expect that the depositary, upon receipt of any payment of principal of, and premium or interest on, a global debt security, will immediately credit participants&#x2019; accounts with payments in amounts proportionate to the respective amounts of book-entry debt securities held by each participant as shown on the records of such depositary. We also expect that payments by participants to owners of beneficial interests in book-entry debt securities held through those participants will be governed by standing customer instructions and customary practices, as is now the case with the securities held for the accounts of customers in bearer form or registered in &#x201c;street name,&#x201d; and will be the responsibility of those participants.

We will issue certificated debt securities in exchange for each global debt security if the depositary is at any time unwilling or unable to continue as depositary or ceases to be a clearing agency registered under the Exchange Act and a successor depositary registered as a clearing agency under the Exchange Act is not appointed by us within 90 days. In addition, we may at any time and in our sole discretion determine not to have the book-entry debt securities of any series represented by one or more global debt securities and, in that event, will issue certificated debt securities in exchange for the global debt securities of that series. Global debt securities will also be exchangeable by the holders for certificated debt securities if an event of default with respect to the book-entry debt securities represented by those global debt securities has occurred and is continuing. Any certificated debt securities issued in exchange for a global debt security will be registered in such name or names as the depositary shall instruct the trustee. We expect that such instructions will be based upon directions received by the depositary from participants with respect to ownership of book-entry debt securities relating to such global debt security.

We have obtained the foregoing information concerning the depositary and the depositary&#x2019;s book-entry system from sources we believe to be reliable, but we take no responsibility for the accuracy of this information.

No Protection in the Event of a Change in Control

Unless we state otherwise in the applicable prospectus supplement, the debt securities will not contain any provisions that may afford holders of the debt securities protection in the event we have a change in control or in the event of a highly leveraged transaction (whether or not such transaction results in a change in control) that could adversely affect holders of debt securities.

Covenants

We will set forth in the applicable prospectus supplement any restrictive covenants applicable to any issue of debt securities.

Subordination

Debt securities of a series may be subordinated, which we refer to as subordinated debt securities, to senior indebtedness (as defined in the applicable prospectus supplement) to the extent set forth in the prospectus supplement relating thereto. To the extent we conduct operations through subsidiaries, the holders of debt securities (whether or not subordinated debt securities) will be structurally subordinated to the creditors of our subsidiaries.

Consolidation, Merger or Sale of Assets

We may not consolidate with or merge with or into, or convey, transfer or lease all or substantially all of our properties and assets to, any person, which we refer to as a successor person, unless:

&#x2022;
we are the surviving corporation or the successor person (if other than our Company) is a corporation organized and validly existing under the laws of any U.S. domestic jurisdiction and expressly assumes our obligations under the debt securities and under the indenture;
&#x2022;
immediately after giving effect to the transaction, no event of default, and no event which, after notice or lapse of time, or both, would become an event of default, shall have occurred and be continuing under the indenture; and
&#x2022;
certain other conditions are met.

Notwithstanding the above, any of our subsidiaries may consolidate with, merge into or transfer all or part of its properties to us.

Events of Default

Event of default means, with respect to any series of debt securities, any of the following:

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default in the payment of any interest upon any debt security of that series when it becomes due and payable, and continuance of that default for a period of 30 days (unless the entire amount of the payment is deposited by us with the trustee or with a paying agent prior to the expiration of the 30-day period);
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default in the payment of principal of any debt security of that series when due and payable;
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default in the performance or breach of any other covenant or warranty by us in the indenture or any debt security (other than a covenant or warranty that has been included in the indenture solely for the benefit of a series of debt securities other than that series), which default continues uncured for a period of 60 days after we receive written notice from the trustee or we and

16

the trustee receive written notice from the holders of not less than 25% in principal amount of the outstanding debt securities of that series as provided in the indenture;
&#x2022;
certain events of bankruptcy, insolvency or reorganization of our company; and
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any other event of default provided with respect to debt securities of that series that is described in the applicable prospectus supplement accompanying this prospectus.

No event of default with respect to a particular series of debt securities (except as to certain events of bankruptcy, insolvency or reorganization) necessarily constitutes an event of default with respect to any other series of debt securities. The occurrence of certain events of default or an acceleration under the indenture may constitute an event of default under certain of our other indebtedness outstanding from time to time.

If an event of default with respect to debt securities of any series outstanding at the time occurs and is continuing, then the trustee or the holders of not less than 25% in principal amount of the outstanding debt securities of that series may, by a notice in writing to us (and to the trustee if given by the holders), declare to be due and payable immediately the principal (or, if the debt securities of that series are discount securities, that portion of the principal amount as may be specified in the terms of that series) of, and accrued and unpaid interest, if any, on all debt securities of that series. In the case of an event of default resulting from certain events of bankruptcy, insolvency or reorganization, the principal (or such specified amount) of and accrued and unpaid interest, if any, on all outstanding debt securities will become and be immediately due and payable without any declaration or other act on the part of the trustee or any holder of outstanding debt securities. At any time after a declaration of acceleration with respect to debt securities of any series has been made, but before a judgment or decree for payment of the money due has been obtained by the trustee, the holders of a majority in principal amount of the outstanding debt securities of that series may rescind and annul the acceleration if all events of default, other than the non-payment of accelerated principal and interest, if any, with respect to debt securities of that series, have been cured or waived as provided in the indenture. We refer you to the prospectus supplement relating to any series of debt securities that are discount securities for the particular provisions relating to acceleration of a portion of the principal amount of such discount securities upon the occurrence of an event of default.

The indenture provides that the trustee will be under no obligation to exercise any of its rights or powers under the indenture, unless the trustee receives indemnity satisfactory to it against any loss, liability or expense. Subject to certain rights of the trustee, the holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee with respect to the debt securities of that series.

No holder of any debt security of any series will have any right to institute any proceeding, judicial or otherwise, with respect to the indenture or for the appointment of a receiver or trustee, or for any remedy under the indenture, unless:

&#x2022;
that holder has previously given to the trustee written notice of a continuing event of default with respect to debt securities of that series; and
&#x2022;
the holders of not less than 25% in principal amount of the outstanding debt securities of that series have made written request, and offered reasonable indemnity, to the trustee to institute the proceeding as trustee, and the trustee has not received from the holders of not less than 25% in principal amount of the outstanding debt securities of that series a direction inconsistent with that request and has failed to institute the proceeding within 60 days.

Notwithstanding the foregoing, the holder of any debt security will have an absolute and unconditional right to receive payment of the principal of and any interest on that debt security on or after the due dates expressed in that debt security and to institute suit for the enforcement of payment.

The indenture requires us, within 120 days after the end of our fiscal year, to furnish to the trustee a statement as to compliance with the indenture. The indenture provides that the trustee may withhold notice to the holders of debt securities of any series of any default or event of default (except in payment on any debt securities of that series) with respect to debt securities of that series if it in good faith determines that withholding notice is in the interest of the holders of those debt securities.

Modification and Waiver

We may modify and amend the indenture with the consent of the holders of at least a majority in principal amount of the outstanding debt securities of each series affected by the modifications or amendments. We may not make any modification or amendment without the consent of the holders of each affected debt security then outstanding if that amendment will:

&#x2022;
reduce the amount of debt securities whose holders must consent to an amendment, supplement or waiver;
&#x2022;
reduce the rate of or extend the time for payment of interest (including default interest) on any debt security;

17

&#x2022;
reduce the principal of or change the fixed maturity of any debt security or reduce the amount of, or postpone the date fixed for, the payment of any sinking fund or analogous obligation with respect to any series of debt securities;
&#x2022;
reduce the principal amount of discount securities payable upon acceleration of maturity;
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waive a default in the payment of the principal of or interest on any debt security (except a rescission of acceleration of the debt securities of any series by the holders of at least a majority in aggregate principal amount of the then outstanding debt securities of that series and a waiver of the payment default that resulted from such acceleration);
&#x2022;
make the principal of or interest on any debt security payable in currency other than that stated in the debt security;
&#x2022;
make any change to certain provisions of the indenture relating to, among other things, the right of holders of debt securities to receive payment of the principal of and interest on those debt securities and to institute a suit for the enforcement of any such payment and to waivers or amendments; or
&#x2022;
waive a redemption payment with respect to any debt security.

Except for certain specified provisions, the holders of at least a majority in principal amount of the outstanding debt securities of any series may on behalf of the holders of all debt securities of that series waive our compliance with provisions of the indenture. The holders of a majority in principal amount of the outstanding debt securities of any series may on behalf of the holders of all the debt securities of such series waive any past default under the indenture with respect to that series and its consequences, except a default in the payment of the principal of or any interest on, any debt security of that series; provided, however, that the holders of a majority in principal amount of the outstanding debt securities of any series may rescind an acceleration and its consequences, including any related payment default that resulted from the acceleration.

Defeasance of Debt Securities and Certain Covenants in Certain Circumstances

Legal Defeasance. The indenture provides that, unless otherwise provided by the terms of the applicable series of debt securities, we may be discharged from any and all obligations in respect of the debt securities of any series (except for certain obligations to register the transfer or exchange of debt securities of such series, to replace stolen, lost or mutilated debt securities of such series, and to maintain paying agencies and certain provisions relating to the treatment of funds held by paying agents). We will be so discharged upon the deposit with the trustee, in trust, of money and/or U.S. government obligations or, in the case of debt securities denominated in a single currency other than U.S. dollars, foreign government obligations, that, through the payment of interest and principal in accordance with their terms, will provide money in an amount sufficient in the opinion of a nationally recognized firm of independent certified public accountants to pay and discharge each installment of principal of and interest on and any mandatory sinking fund payments in respect of the debt securities of that series on the stated maturity of those payments in accordance with the terms of the indenture and those debt securities.

This discharge may occur only if, among other things, we have delivered to the trustee an opinion of counsel stating that we have received from, or there has been published by, the United States Internal Revenue Service a ruling or, since the date of execution of the indenture, there has been a change in the applicable United States federal income tax law, in either case to the effect that, and based thereon such opinion shall confirm that, the beneficial owners of the debt securities of that series will not recognize income, gain or loss for United States federal income tax purposes as a result of the deposit, defeasance and discharge and will be subject to United States federal income tax on the same amounts and in the same manner and at the same times as would have been the case if the deposit, defeasance and discharge had not occurred.

Defeasance of Certain Covenants. The indenture provides that, unless otherwise provided by the terms of the applicable series of debt securities, upon compliance with certain conditions:

&#x2022;
we may omit to comply with the covenant described under the heading &#x201c;&#x2014;Consolidation, Merger or Sale of Assets&#x201d; and certain other covenants set forth in the indenture, as well as any additional covenants that may be set forth in the applicable prospectus supplement; and
&#x2022;
any omission to comply with those covenants will not constitute a default or an event of default with respect to the debt securities of that series, or covenant defeasance.

The conditions include:

&#x2022;
depositing with the trustee money and/or U.S. government obligations or, in the case of debt securities denominated in a single currency other than U.S. dollars, foreign government obligations, that, through the payment of interest and principal in accordance with their terms, will provide money in an amount sufficient in the opinion of a nationally recognized firm of independent certified public accountants to pay and discharge each installment of principal of and interest on and any mandatory sinking fund payments in respect of the debt securities of that series on the stated maturity of those payments in accordance with the terms of the indenture and those debt securities; and

18

&#x2022;
delivering to the trustee an opinion of counsel to the effect that the beneficial owners of the debt securities of that series will not recognize income, gain or loss for United States federal income tax purposes as a result of the deposit and related covenant defeasance and will be subject to United States federal income tax on the same amounts and in the same manner and at the same times as would have been the case if the deposit and related covenant defeasance had not occurred.

Covenant Defeasance and Events of Default. In the event we exercise our option to effect covenant defeasance with respect to any series of debt securities and the debt securities of that series are declared due and payable because of the occurrence of any event of default, the amount of money and/or U.S. government obligations or foreign government obligations on deposit with the trustee will be sufficient to pay amounts due on the debt securities of that series at the time of their stated maturity but may not be sufficient to pay amounts due on the debt securities of that series at the time of the acceleration resulting from the event of default. In such a case, we would remain liable for those payments.

&#x201c;Foreign Government Obligations&#x201d; means, with respect to debt securities of any series that are denominated in a currency other than U.S. dollars:

&#x2022;
direct obligations of the government that issued or caused to be issued such currency for the payment of which obligations its full faith and credit is pledged which are not callable or redeemable at the option of the issuer thereof; or
&#x2022;
obligations of a person controlled or supervised by or acting as an agency or instrumentality of that government, the timely payment of which is unconditionally guaranteed as a full faith and credit obligation by that government which are not callable or redeemable at the option of the issuer thereof.

Regarding the Trustee

The indenture provides that, except during the continuance of an event of default, the trustee will perform only such duties as are specifically set forth in the indenture. During the existence of an event of default, the trustee will exercise such rights and powers vested in it under the indenture and use the same degree of care and skill in its exercise as a prudent person would exercise or use under the circumstances in the conduct of such person&#x2019;s own affairs.

The indenture and provisions of the Trust Indenture Act of 1939, as amended, that are incorporated by reference therein contain limitations on the rights of the trustee, should it become one of our creditors, to obtain payment of claims in certain cases or to realize on certain property received by it in respect of any such claim as security or otherwise. The trustee is permitted to engage in other transactions with us or any of our affiliates; provided, however, that if it acquires any conflicting interest (as defined in the indenture or in the Trust Indenture Act of 1939, as amended), it must eliminate such conflict or resign.

Regarding Payments and Paying Agents

Unless we state otherwise in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities are registered at the close of business on the regular record date for the interest payment.

We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agent designated by us, except that unless we indicate otherwise in the applicable prospectus supplement, we will make interest payments by check that we will mail to the holder or by wire transfer to certain holders. Unless we indicate otherwise in the applicable prospectus supplement, we will designate the corporate trust office of the trustee as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the trustee for the payment of the principal of or any premium or interest on any debt securities that remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the debt security thereafter may look only to us for payment thereof.

Governing Law

The indenture and the debt securities will be governed by, and construed in accordance with, the internal laws of the State of New York.

19

DESCRIPTION OF WARRANTS

The following description, together with the additional information we may include in the applicable prospectus supplements and free-writing prospectuses we have authorized for use in connection with a specific offering, summarizes the material terms and provisions of the warrants that we may offer under this prospectus, which may consist of warrants to purchase common stock, preferred stock or debt securities and may be issued in one or more series.

Warrants may be issued independently or together with common stock, preferred stock or debt securities offered by any prospectus supplement, and may be attached to or separate from those securities. While the terms we have summarized below will apply generally to any warrants that we may offer under this prospectus, we will describe the particular terms of any series of warrants that we may offer in more detail in the applicable prospectus supplement and any applicable free writing prospectus we authorize for use in connection with the specific offering. The terms of any warrants offered under a prospectus supplement may differ from the terms described below.

We will file as exhibits to the registration statement of which this prospectus is a part, or we will incorporate by reference from reports that we file with the SEC, the form of warrant agreement, if any, including a form of warrant certificate, that describes the terms of the particular series of warrants we are offering. The following summaries of material provisions of the warrants and the warrant agreements are subject to, and qualified in their entirety by reference to, all the provisions of the warrant agreement and warrant certificate applicable to the particular series of warrants that we may offer under this prospectus. We urge you to read the applicable prospectus supplements related to the particular series of warrants that we may offer under this prospectus, as well as any related free-writing prospectuses we have authorized for use in connection with a specific offering, and the complete warrant agreements and warrant certificates that contain the terms of the warrants.

General Matters

We will describe in the applicable prospectus supplement the terms relating to a series of warrants being offered, including:

&#x2022;
the title of such securities;
&#x2022;
the offering price or prices and aggregate number of warrants offered;
&#x2022;
the currency or currencies for which the warrants may be purchased;
&#x2022;
if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;
&#x2022;
if applicable, the date on and after which the warrants and the related securities will be separately transferable;
&#x2022;
if applicable, the minimum or maximum amount of such warrants which may be exercised at any one time;
&#x2022;
in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant and the price at which, and currency in which, this principal amount of debt securities may be purchased upon such exercise;
&#x2022;
in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which, and the currency in which, these shares may be purchased upon such exercise;
&#x2022;
the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreements and the warrants;
&#x2022;
the terms of any rights to redeem or call the warrants;
&#x2022;
the terms of any rights to force the exercise of the warrants;
&#x2022;
any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;
&#x2022;
the dates on which the right to exercise the warrants will commence and expire;
&#x2022;
the manner in which the warrant agreements and warrants may be modified;
&#x2022;
a discussion of any material or special United States federal income tax consequences of holding or exercising the warrants;
&#x2022;
the terms of the securities issuable upon exercise of the warrants; and
&#x2022;
any other specific terms, preferences, rights or limitations of or restrictions on the warrants.

Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including:

20

&#x2022;
in the case of warrants to purchase debt securities, the right to receive payments of principal of, or premium, if any, or interest on, the debt securities purchasable upon exercise or to enforce covenants in the applicable indenture; or
&#x2022;
in the case of warrants to purchase common stock or preferred stock, the right to receive dividends, if any, or payments upon our liquidation, dissolution or winding up or to exercise voting rights, if any.

Exercise of Warrants

Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent in connection with the exercise of the warrant.

Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant certificate are exercised, then we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.

Governing Law

Unless we provide otherwise in the applicable prospectus supplement, the warrants and warrant agreements, and any claim, controversy or dispute arising under or related to the warrants or warrant agreements, will be governed by and construed in accordance with the laws of the State of New York.

Enforceability of Rights by Holders of Warrants

Each warrant agent will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.

Warrant Agreement Will Not Be Qualified Under Trust Indenture Act

No warrant agreement will be qualified as an indenture, and no warrant agent will be required to qualify as a trustee, under the Trust Indenture Act. Therefore, holders of warrants issued under a warrant agreement will not have the protection of the Trust Indenture Act with respect to their warrants.

Calculation Agent

Calculations relating to warrants may be made by a calculation agent, an institution that we appoint as our agent for this purpose. The prospectus supplement for a particular warrant will name the institution that we have appointed to act as the calculation agent for that warrant as of the original issue date for that warrant. We may appoint a different institution to serve as calculation agent from time to time after the original issue date without the consent or notification of the holders.

The calculation agent&#x2019;s determination of any amount of money payable or securities deliverable with respect to a warrant will be final and binding in the absence of manifest error.

21

DESCRIPTION OF RIGHTS

General

We may issue rights to purchase common stock, preferred stock, debt securities, warrants, units and/or any of the other securities described in this prospectus. We may offer rights separately or together with one or more additional rights, preferred stock, common stock, debt securities, warrants, units or any combination of those securities in the form of units, as described in the applicable prospectus supplement. Each series of rights will be issued under a separate rights agreement to be entered into between us and a bank or trust company, as rights agent. This prospectus and any accompanying prospectus supplement will contain the material terms and conditions for each right. The accompanying prospectus supplement may add, update or change the terms and conditions of the rights as described in this prospectus.

We will describe in the applicable prospectus supplement the terms and conditions of the issue of rights being offered, the rights agreement relating to the rights and the rights certificates representing the rights, including, as applicable:

&#x2022;
the title of the rights;
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the date of determining the stockholders entitled to the rights distribution;
&#x2022;
the title, aggregate number or amount of underlying securities purchasable upon exercise of the rights;
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the exercise price;
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the currencies in which the rights are being offered;
&#x2022;
the aggregate number of rights issued;
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whether the rights are transferable and the date, if any, on and after which the rights will be separately transferable;
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the date on which the right to exercise the rights will commence and the date on which the right to exercise the rights will expire;
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the method by which holders of rights will be entitled to exercise;
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the conditions to the completion of the offering, if any;
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the withdrawal, termination and cancellation rights, if any;
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whether there are backstop or standby purchasers and the terms of their commitment, if any;
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whether stockholders are entitled to oversubscription rights, if any; and
&#x2022;
any other terms of the rights, including terms, procedures and limitations relating to the distribution, exchange and exercise of the rights, as applicable, including any provisions for modifying any of the terms of the rights.

Exercise of Rights

Each right will entitle the holder of rights to purchase for cash the principal amount of shares of common stock, preferred stock, debt securities, warrants, units or other securities, as applicable, at the exercise price provided in the applicable prospectus supplement. Rights may be exercised at any time up to the close of business on the expiration date for the rights provided in the applicable prospectus supplement. After the close of business on the expiration date, all unexercised rights will be void.

Holders may exercise rights as described in the applicable prospectus supplement. Upon receipt of payment and the rights certificate properly completed and duly executed at the corporate trust office of the rights or subscription agent or any other office indicated in the applicable prospectus supplement, we will, as soon as practicable, forward the shares of common stock, preferred stock, debt securities, warrants, units or other securities, as applicable, purchasable upon exercise of the rights. If less than all of the rights issued in any rights offering are exercised, we may offer any unsubscribed securities directly to persons other than stockholders, to or through agents, underwriters, brokers or dealers or through a combination of such methods, including pursuant to standby underwriting arrangements, as described in the applicable prospectus supplement.

The rights agent for any rights we offer will be set forth in the applicable prospectus supplement.

22

DESCRIPTION OF UNITS

We may issue units consisting of any combination of the other types of securities offered under this prospectus in one or more series. We may evidence each series of units by unit certificates that we will issue under a separate agreement. We may enter into unit agreements with a unit agent. Each unit agent will be a bank or trust company that we select. We will indicate the name and address of the unit agent in the applicable prospectus supplement relating to a particular series of units.

The following description, together with the additional information included in the applicable prospectus supplement, summarizes the general features of the units that we may offer under this prospectus. You should read any prospectus supplement and any free-writing prospectus we authorize for use in connection with a specific offering of units, as well as the complete unit agreements that contain the terms of the units. Specific unit agreements will contain additional important terms and provisions, and we will file as an exhibit to the registration statement of which this prospectus is a part, or we will incorporate by reference from another report that we file with the SEC, the form of each unit agreement relating to units offered under this prospectus.

If we offer any units, certain terms of that series of units will be described in the applicable prospectus supplement, including, without limitation, the following, as applicable:

&#x2022;
the title of the series of units;
&#x2022;
identification and description of the separate constituent securities comprising the units;
&#x2022;
the price or prices at which the units will be issued;
&#x2022;
the date, if any, on and after which the constituent securities comprising the units will be separately transferable;
&#x2022;
a discussion of certain U.S. federal income tax considerations applicable to the units; and
&#x2022;
any other terms of the units and their constituent securities.

23

DESCRIPTION OF DEPOSITARY SHARES

General

We may issue depositary shares, each of which will represent a fractional interest of a share of a particular series of preferred stock, as specified in the applicable prospectus supplement. We will deposit with a depositary, referred to as the preferred stock depositary, shares of preferred stock of each series represented by depositary shares. We will enter into a deposit agreement with the preferred stock depositary and holders from time to time of the depositary receipts issued by the preferred stock depositary which evidence the depositary shares. Subject to the terms of the deposit agreement, each owner of a depositary receipt will be entitled, in proportion to the holder&#x2019;s fractional interest in the preferred stock, to all the rights and preferences of the series of the preferred stock represented by the depositary shares, including dividend, voting, conversion, redemption and liquidation rights.

Immediately after we issue and deliver the preferred stock to a preferred stock depositary, we will cause the preferred stock depositary to issue the depositary receipts on our behalf. You may obtain copies of the applicable form of deposit agreement and depositary receipt from us upon request. The statements made in this section relating to the deposit agreement and the depositary receipts are summaries only. These summaries are not complete and we may modify any of the terms of the depositary shares described in this prospectus in a prospectus supplement. To the extent the information contained in the prospectus supplement differs from this summary description, you should rely on the information in the prospectus supplement. For more detail, we refer you to the deposit agreement, which we will file as an exhibit to, or incorporate by reference in, the registration statement.

Dividends and Other Distributions

The preferred stock depositary will distribute all cash dividends or other cash distributions received relating to the preferred stock to the record holders of depositary receipts in proportion to the number of the depositary receipts owned by the holders, subject to the obligations of holders to file proofs, certificates and other information and to pay certain charges and expenses to the preferred stock depositary.

In the event of a distribution other than in cash, the preferred stock depositary will distribute property received by it to the record holders of depositary receipts in proportion to the number of the depositary receipts owned by the holders, unless the preferred stock depositary determines that it is not feasible to make the distribution, in which case the preferred stock depositary may, with our approval, sell the property and distribute the net proceeds from the sale to the holders.

No distribution will be made relating to any depositary share that represents any preferred stock converted into other securities.

Withdrawal of Stock

Assuming we have not previously called for redemption or converted into other securities the related depositary shares, upon surrender of the depositary receipts at the corporate trust office of the preferred stock depositary, the holders will be entitled to delivery at that office of the number of whole or fractional shares of the preferred stock and any money or other property represented by the depositary shares. Holders of depositary receipts will be entitled to receive shares of the related preferred stock as specified in the applicable prospectus supplement, but holders of the shares of preferred stock will no longer be entitled to receive depositary shares.

Redemption of Depositary Shares

Whenever we redeem shares of preferred stock held by the preferred stock depositary, the preferred stock depositary will concurrently redeem the number of depositary shares representing shares of the preferred stock so redeemed, provided we have paid the applicable redemption price for the preferred stock to be redeemed plus an amount equal to any accrued and unpaid dividends to the date fixed for redemption. The redemption price per depositary share will be equal to the corresponding proportion of the redemption price and any other amounts per share payable relating to the preferred stock. If fewer than all the depositary shares are to be redeemed, the depositary shares to be redeemed will be selected pro rata or by any other equitable method determined by us.

From and after the date fixed for redemption:

&#x2022;
all dividends relating to the shares of preferred stock called for redemption will cease to accrue;
&#x2022;
the depositary shares called for redemption will no longer be deemed to be outstanding; and
&#x2022;
all rights of the holders of the depositary receipts evidencing the depositary shares called for redemption will cease, except the right to receive any moneys payable upon the redemption and any money or other property to which the holders of the depositary receipts were entitled upon redemption and surrender to the preferred stock depositary.

24

Any funds we deposit with the preferred stock depositary for redemption of depositary shares that the holders fail to redeem will be returned to us after a period of two years from the date the funds are deposited.

Voting of the Preferred Stock

Upon receipt of notice of any meeting at which the holders of the preferred stock are entitled to vote, the preferred stock depositary will mail the information contained in the notice of meeting to the record holders of the depositary receipts. Each record holder of these depositary receipts on the record date, which will be the same date as the record date for the preferred stock, will be entitled to instruct the preferred stock depositary as to the exercise of the voting rights pertaining to the amount of preferred stock represented by the holder&#x2019;s depositary shares. The preferred stock depositary will vote the amount of preferred stock represented by the depositary shares in accordance with the instructions, and we will agree to take all reasonable action necessary to enable the preferred stock depositary to do so. The preferred stock depositary will abstain from voting the amount of preferred stock represented by the depositary shares for which it does not receive specific instructions from the holders of depositary receipts evidencing the depositary shares. The preferred stock depositary will not be responsible for any failure to carry out any instruction to vote, or for the manner or effect of any vote made, as long as the action or non-action is in good faith and does not result from the preferred stock depositary&#x2019;s negligence or willful misconduct.

Liquidation Preference

In the event that we voluntarily or involuntarily liquidate, dissolve or wind up, the holders of each depositary receipt will be entitled to the fraction of the liquidation preference accorded each share of preferred stock represented by the depositary shares, as specified in the applicable prospectus supplement.

Conversion of Depositary Shares

The depositary shares will not be convertible into common stock or any of our other securities or property, unless we so specify in the applicable prospectus supplement relating to an offering of depositary shares.

Amendment and Termination of the Deposit Agreement

We may amend the form of depositary receipt and any provision of the deposit agreement at any time by agreement with the preferred stock depositary. However, any amendment that imposes or increases any fees, taxes or other charges payable by the holders of depositary receipts, other than taxes and other governmental charges, fees and other expenses payable by the holders as described below under &#x201c;&#x2014;Charges of Preferred Stock Depositary&#x201d;, or that otherwise prejudices any substantial existing right of holders of depositary receipts, will not take effect as to outstanding depositary receipts until the expiration of 30 days after notice of the amendment has been mailed to the record holders of outstanding depositary receipts.

When we direct the preferred stock depositary to do so, the preferred stock depositary will terminate the deposit agreement by mailing a notice of termination to the record holders of all depositary receipts then outstanding at least 30 days prior to the date fixed in the notice for termination. In addition, the preferred stock depositary may terminate the deposit agreement if at any time 45 days have passed since the preferred stock depositary has delivered to us a written notice of its election to resign and a successor preferred stock depositary has not been appointed and accepted its appointment. If any depositary receipts remain outstanding after the date of termination, the preferred stock depositary thereafter will discontinue the transfer of depositary receipts, will suspend the distribution of dividends to the holders thereof, and will not give any further notices, other than the notice of termination, or perform any further acts under the deposit agreement, except as provided below and except that the preferred stock depositary will continue to collect dividends on the preferred stock and other distributions with respect to the preferred stock and will continue to deliver the preferred stock together with any dividends and distributions and the net proceeds of any sales of rights, preferences, privileges or other property, without liability for interest thereon, in exchange for any depositary receipts that are surrendered. At any time after the expiration of two years from the date of termination, the preferred stock depositary may sell the preferred stock then held by it at public or private sales, at such place or places and upon such terms as it deems proper and may thereafter hold the net proceeds of any such sale, together with any money or other property then held by it, without liability for interest thereon, for the pro rata benefit of the holders of depositary receipts that have not been surrendered.

In addition, the deposit agreement will automatically terminate if:

&#x2022;
all outstanding depositary shares have been redeemed; or
&#x2022;
there has been a final distribution of the related preferred stock in connection with our liquidation, dissolution or winding up and the distribution has been distributed to the holders of depositary receipts evidencing the depositary shares representing the preferred stock.

25

Charges of Preferred Stock Depositary

We will pay all fees, charges and expenses of the preferred stock depositary in connection with its performance of the deposit agreement, except for any taxes and other governmental charges and except as provided in the deposit agreement. Holders of depositary receipts will pay the fees and expenses of the preferred stock depositary for any duties requested by the holders to be performed which are outside those expressly provided for in the deposit agreement.

Resignation and Removal of Preferred Stock Depositary

The preferred stock depositary may resign at any time by delivering to us notice of its election to do so, and we may at any time remove the preferred stock depositary. Any resignation or removal of the acting preferred stock depositary will take effect upon our appointment of a successor preferred stock depositary. We must appoint a successor preferred stock depositary within 45 days after delivery of the notice of resignation or removal.

Miscellaneous

The preferred stock depositary will make available for inspection to holders of depositary receipts any reports and communications the preferred stock depositary receives from us relating to the preferred stock.

We will not be liable, nor will the preferred stock depositary be liable, if we are prevented from or delayed in, by law or any circumstances beyond our control, performing our obligations under the deposit agreement. Our obligations and the obligations of the preferred stock depositary under the deposit agreement will be limited to performing our duties in good faith and without negligence or willful misconduct. We will not be obligated, nor will the preferred stock depositary be obligated, to prosecute or defend any legal proceeding relating to any depositary receipts, depositary shares or shares of preferred stock represented by depositary shares unless satisfactory indemnity is furnished to us. We may rely, and the preferred stock depositary may rely, on written advice of counsel or accountants, or information provided by persons presenting shares of preferred stock represented by depositary shares for deposit, holders of depositary receipts or other persons we believe in good faith to be competent to give this information, and on documents we believe in good faith to be genuine and signed by a proper party.

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LEGAL OWNERSHIP OF SECURITIES

We can issue securities in registered form or in the form of one or more global securities. We describe global securities in greater detail below. We refer to those persons who have securities registered in their own names on the books that we or any applicable trustee or depositary maintain for this purpose as the &#x201c;holders&#x201d; of those securities. These persons are the legal holders of the securities. We refer to those persons who, indirectly through others, own beneficial interests in securities that are not registered in their own names, as &#x201c;indirect holders&#x201d; of those securities. As we discuss below, indirect holders are not legal holders, and investors in securities issued in book-entry form or in street name will be indirect holders.

Book-Entry Holders

We may issue securities in book-entry form only, as we will specify in the applicable prospectus supplement. This means securities may be represented by one or more global securities registered in the name of a financial institution that holds them as depositary on behalf of other financial institutions that participate in the depositary&#x2019;s book-entry system. These participating institutions, which are referred to as participants, in turn, hold beneficial interests in the securities on behalf of themselves or their customers.

Only the person in whose name a security is registered is recognized as the holder of that security. Global securities will be registered in the name of the depositary or its participants. Consequently, for global securities, we will recognize only the depositary as the holder of the securities, and we will make all payments on the securities to the depositary. The depositary passes along the payments it receives to its participants, which in turn pass the payments along to their customers who are the beneficial owners. The depositary and its participants do so under agreements they have made with one another or with their customers; they are not obligated to do so under the terms of the securities.

As a result, investors in a global security will not own securities directly. Instead, they will own beneficial interests in a global security, through a bank, broker or other financial institution that participates in the depositary&#x2019;s book-entry system or holds an interest through a participant. As long as the securities are issued in global form, investors will be indirect holders, and not legal holders, of the securities.

Street Name Holders

We may terminate a global security in certain situations, as described under &#x201c;&#x2014;Special Situations When a Global Security Will Be Terminated&#x201d;, or issue securities that are not issued in global form. In these cases, investors may choose to hold their securities in their own names or in &#x201c;street name&#x201d;. Securities held by an investor in street name would be registered in the name of a bank, broker or other financial institution that the investor chooses, and the investor would hold only a beneficial interest in those securities through an account he or she maintains at that institution.

For securities held in street name, we or any applicable trustee or depositary will recognize only the intermediary banks, brokers and other financial institutions in whose names the securities are registered as the holders of those securities, and we or any such trustee or depositary will make all payments on those securities to them. These institutions pass along the payments they receive to their customers who are the beneficial owners but only because they agree to do so in their customer agreements or because they are legally required to do so. Investors who hold securities in street name will be indirect holders, not holders, of those securities.

Legal Holders

Our obligations, as well as the obligations of any applicable trustee or third party employed by us or a trustee, run only to the legal holders of the securities. We do not have obligations to investors who hold beneficial interests in global securities, in street name or by any other indirect means. This will be the case whether an investor chooses to be an indirect holder of a security or has no choice because we are issuing the securities only in global form.

For example, once we make a payment or give a notice to the legal holder, we have no further responsibility for the payment or notice even if that legal holder is required, under agreements with its participants or customers or by law, to pass the payment or notice along to the indirect holders but does not do so. Similarly, we may want to obtain the approval of the holders to amend an indenture, to relieve us of the consequences of a default or of our obligation to comply with a particular provision of an indenture, or for other purposes. In such an event, we would seek approval only from the legal holders, and not the indirect holders, of the securities. Whether and how the legal holders contact the indirect holders is up to the legal holders.

Special Considerations for Indirect Holders

If you hold securities through a bank, broker or other financial institution, either in book-entry form because the securities are represented by one or more global securities or in street name, you should check with your own institution to find out:

&#x2022;
how it handles securities payments and notices;
&#x2022;
whether it imposes fees or charges;
&#x2022;
how it would handle a request for the holders&#x2019; consent, if ever required;

27

&#x2022;
whether and how you can instruct it to send you securities registered in your own name so you can be a holder, if that is permitted in the future;
&#x2022;
how it would exercise rights under the securities if there were a default or other event triggering the need for holders to act to protect their interests; and
&#x2022;
if the securities are in book-entry form, how the depositary&#x2019;s rules and procedures will affect these matters.

Global Securities

A global security is a security that represents one or any other number of individual securities held by a depositary. Generally, all securities represented by the same global securities will have the same terms.

Each security issued in book-entry form will be represented by a global security that we issue to, deposit with and register in the name of a financial institution or its nominee that we select. The financial institution that we select for this purpose is called the depositary. Unless we specify otherwise in the applicable prospectus supplement, The Depository Trust Company, New York, New York, known as DTC, will be the depositary for all securities issued in book-entry form.

A global security may not be transferred to or registered in the name of anyone other than the depositary, its nominee or a successor depositary, unless special termination situations arise. We describe those situations below under &#x201c;&#x2014;Special Situations When a Global Security Will Be Terminated&#x201d;. As a result of these arrangements, the depositary, or its nominee, will be the sole registered owner and legal holder of all securities represented by a global security, and investors will be permitted to own only beneficial interests in a global security. Beneficial interests must be held by means of an account with a broker, bank or other financial institution that in turn has an account with the depositary or with another institution that does. Thus, an investor whose security is represented by a global security will not be a legal holder of the security, but only an indirect holder of a beneficial interest in the global security.

If the prospectus supplement for a particular security indicates that the security will be issued as a global security, then the security will be represented by a global security at all times unless and until the global security is terminated. If termination occurs, we may issue the securities through another book-entry clearing system or decide that the securities may no longer be held through any book-entry clearing system.

Special Considerations for Global Securities

As an indirect holder, an investor&#x2019;s rights relating to a global security will be governed by the account rules of the investor&#x2019;s financial institution and of the depositary, as well as general laws relating to securities transfers. We do not recognize an indirect holder as a holder of securities and instead deal only with the depositary that holds the global security.

If securities are issued only as global securities, an investor should be aware of the following:

&#x2022;
an investor cannot cause the securities to be registered in his or her name, and cannot obtain non-global certificates for his or her interest in the securities, except in the special situations described below;
&#x2022;
an investor will be an indirect holder and must look to his or her own bank or broker for payments on the securities and protection of his or her legal rights relating to the securities, as described above;
&#x2022;
an investor may not be able to sell interests in the securities to some insurance companies and to other institutions that are required by law to own their securities in non-book-entry form;
&#x2022;
an investor may not be able to pledge his or her interest in the global security in circumstances where certificates representing the securities must be delivered to the lender or other beneficiary of the pledge in order for the pledge to be effective;
&#x2022;
the depositary&#x2019;s policies, which may change from time to time, will govern payments, transfers, exchanges and other matters relating to an investor&#x2019;s interest in the global security;
&#x2022;
we and any applicable trustee have no responsibility for any aspect of the depositary&#x2019;s actions or for its records of ownership interests in the global security, nor will we or any applicable trustee supervise the depositary in any way;
&#x2022;
the depositary may, and we understand that DTC will, require that those who purchase and sell interests in the global security within its book-entry system use immediately available funds, and your broker or bank may require you to do the same; and
&#x2022;
financial institutions that participate in the depositary&#x2019;s book-entry system, and through which an investor holds its interest in the global security, may also have their own policies affecting payments, notices and other matters relating to the securities.

There may be more than one financial intermediary in the chain of ownership for an investor. We do not monitor and are not responsible for the actions of any of those intermediaries.

Special Situations When a Global Security Will Be Terminated

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In a few special situations described below, a global security will terminate and interests in it will be exchanged for physical certificates representing those interests. After that exchange, the choice of whether to hold securities directly or in street name will be up to the investor. Investors must consult their own banks or brokers to find out how to have their interests in securities transferred to their own names, so that they will be direct holders. The rights of holders and street name investors are described above.

A global security will terminate when the following special situations occur:

&#x2022;
if the depositary notifies us that it is unwilling, unable or no longer qualified to continue as depositary for that global security and we do not appoint another institution to act as depositary within 90 days;
&#x2022;
if we notify any applicable trustee that we wish to terminate that global security; or
&#x2022;
if an event of default has occurred with regard to securities represented by that global security and has not been cured or waived.

The applicable prospectus supplement may also list additional situations for terminating a global security that would apply only to the particular series of securities covered by the prospectus supplement. When a global security terminates, the depositary, and neither we nor any applicable trustee, is responsible for deciding the names of the institutions that will be the initial direct holders.

29

PLAN OF DISTRIBUTION

We may sell the securities from time to time pursuant to underwritten public offerings, direct sales to the public, &#x201c;at the market&#x201d; offerings, negotiated transactions, block trades or a combination of these methods. We may sell the securities to or through underwriters or dealers, through agents, directly to one or more purchasers or through any combination of the foregoing. We may distribute securities from time to time in one or more transactions:

&#x2022;
at a fixed price or prices, which may be changed;
&#x2022;
at market prices prevailing at the time of sale;
&#x2022;
at prices related to such prevailing market prices; or
&#x2022;
at negotiated prices.

In addition, we may issue the securities as a dividend or distribution to our existing securityholders.

A prospectus supplement or supplements (and any related free writing prospectus that we may have authorized for use in connection with a specific offering) will describe the terms of the offering of the securities, including, to the extent applicable:

&#x2022;
the name or names of the agents, dealers or underwriters, if any;
&#x2022;
the purchase price of the securities or other consideration therefor, and the proceeds, if any, we will receive from the sale;
&#x2022;
any over-allotment options under which underwriters may purchase additional securities from us;
&#x2022;
any agency fees or underwriting discounts and other items constituting agents&#x2019; or underwriters&#x2019; compensation;
&#x2022;
any public offering price;
&#x2022;
any discounts or concessions allowed or re-allowed or paid to dealers; and
&#x2022;
any securities exchange or market on which the securities may be listed.

Only underwriters named in the prospectus supplement will be underwriters of the securities offered by the prospectus supplement.

If underwriters or agents are used in the sale of the securities in respect of which this prospectus is delivered, we will enter into an underwriting agreement or other agreement with them at the time of sale to them, and we will set forth in the prospectus supplement relating to such offering the names of the underwriters or agents and the terms of the related agreement with them.

We may directly solicit offers to purchase securities or agents may be designated to solicit such offers. We will, in the prospectus supplement relating to such offering, name any agent that could be viewed as an underwriter under the Securities Act and describe any commissions that we must pay. Any such agent will be acting on a best efforts basis for the period of its appointment or, if indicated in the applicable prospectus supplement, on a firm commitment basis. This prospectus may be used in connection with any offering of our securities through any of these methods or other methods described in the applicable prospectus supplement.

We may authorize agents or underwriters to solicit offers by certain types of institutional investors to purchase securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. We will describe the conditions to these contracts and the commissions we must pay for solicitation of these contracts in the prospectus supplement.

If a dealer is utilized in the sale of the securities in respect of which the prospectus is delivered, we will sell such securities to the dealer, as principal. The dealer may then resell such securities to the public at varying prices to be determined by such dealer at the time of resale.

We may provide agents and underwriters with indemnification against civil liabilities, including liabilities under the Securities Act, or contribution with respect to payments that the agents or underwriters may make with respect to these liabilities. Agents and underwriters may engage in transactions with, or perform services for, us in the ordinary course of business.

In order to facilitate the offering of the securities, any underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the securities or any other securities the prices of which may be used to determine payments on such securities. Specifically, any underwriters may over-allot in connection with the offering, creating a short position for their own accounts.

30

In addition, to cover over-allotments or to stabilize the price of the securities or of any such other securities, the underwriters may bid for, and purchase, the securities or any such other securities in the open market. Finally, in any offering of the securities through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allowed to an underwriter or a dealer for distributing the securities in the offering if the syndicate repurchases previously distributed securities in transactions to cover syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of the securities above independent market levels. Any such underwriters are not required to engage in these activities and may end any of these activities at any time.

The securities may be new issues of securities and may have no established trading market. The securities may or may not be listed on a national securities exchange. We can make no assurance as to the liquidity of or the existence of trading markets for any of the securities.

The specific terms of any lock up provisions in respect of any given offering will be described in the applicable prospectus supplement.

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LEGAL MATTERS

Unless otherwise indicated in the applicable prospectus supplement, the validity of the securities offered by this prospectus, and any supplement thereto, will be passed upon for us by Paul Hastings LLP, Palo Alto, California.

EXPERTS

The consolidated financial statements of Viking Therapeutics, Inc. and Subsidiaries as of December 31, 2025 and for the year then ended, incorporated in this prospectus by reference from Viking Therapeutics, Inc.&#x2019;s Annual Report on Form 10&#x2011;K for the year ended December 31, 2025, have been audited by CBIZ CPAs P.C., an independent registered public accounting firm, as stated in its report thereon, and are incorporated herein by reference in reliance upon such report and upon the authority of such firm as experts in auditing and accounting.

The consolidated financial statements of Viking Therapeutics, Inc. and Subsidiaries as of December 31, 2024 and for the year then ended, incorporated in this prospectus by reference from Viking Therapeutics, Inc.&#x2019;s Annual Report on Form 10&#x2011;K for the year ended December 31, 2025, have been audited by Marcum LLP, an independent registered public accounting firm, as stated in its report thereon, and are incorporated herein by reference in reliance upon such report and upon the authority of such firm as experts in auditing and accounting.

WHERE YOU CAN FIND MORE INFORMATION

We are a reporting company and file annual, quarterly and current reports, proxy statements and other information with the SEC. We have filed with the SEC a registration statement on Form S-3 under the Securities Act with respect to the securities being offered under this prospectus. This prospectus does not contain all of the information set forth in the registration statement and the exhibits to the registration statement. For further information with respect to us and the securities being offered under this prospectus, we refer you to the registration statement and the exhibits and schedules filed as a part of the registration statement. The SEC maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC, including Viking Therapeutics, Inc. The SEC&#x2019;s Internet site can be found at http://www.sec.gov.

32

IMPORTANT INFORMATION INCORPORATED BY REFERENCE

The SEC allows us to &#x201c;incorporate by reference&#x201d; information into this prospectus, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The documents incorporated by reference into this prospectus contain important information that you should read about us.

The following documents are incorporated by reference into this prospectus:

(a)

Our Annual Report on Form 10-K for the fiscal year ended December 31, 2025, filed with the SEC on February 11, 2026;

(b)

The information specifically incorporated by reference into our Annual Report on Form 10-K for the fiscal year ended December 31, 2025 from our Definitive Proxy Statement on Schedule 14A, filed with the SEC on April 1, 2026;

(c)

Our Quarterly Report on Form 10-Q for the quarter ended March 31, 2026, filed with the SEC on April 30, 2026;

(d)

Our Quarterly Report on Form 10-Q for the quarter ended June 30, 2026, filed with the SEC on July 29, 2026;

(e)

Our Current Report on Form 8-K filed with the SEC on May 26, 2026; and

(f)

The description of our common stock set forth in our Registration Statement on Form 8-A (File No. 001-37355), filed with the SEC on April 23, 2015, including any amendments or reports filed for the purpose of updating such description, including the description of common stock contained in Exhibit 4.2 of our Annual Report on Form 10-K for the fiscal year ended December 31, 2022, filed with the SEC on February 10, 2023.

We also incorporate by reference any future filings (other than current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items unless such Form 8-K expressly provides to the contrary) made with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, including those made after the date of the initial filing of the registration statement of which this prospectus is a part, until we file a post-effective amendment that indicates the termination of the offering of the securities made by this prospectus and will become a part of this prospectus from the respective dates that such documents are filed with the SEC. Any statement contained herein or in a document incorporated, or deemed to be incorporated, by reference herein shall be deemed to be modified or superseded to the extent that a statement contained herein or in any other subsequently filed document that also is, or is deemed to be, incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus.

Documents incorporated by reference are available from us, without charge. You may obtain documents incorporated by reference in this prospectus by requesting them in writing or by telephone at the following address:

Viking Therapeutics, Inc.

9920 Pacific Heights Blvd, Suite 500

San Diego, California 92121

Telephone Number: (858) 704-4660

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$

% Convertible Senior Notes due 2032


________________________________

PROSPECTUS SUPPLEMENT
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Morgan Stanley J.P. Morgan

, 2026

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