Supplemental Prospectus (Form 424B5)

As Filed Pursuant to Rule 424(b)(5)
Registration No. 333-284510

PROSPECTUS SUPPLEMENT

(To Prospectus Supplement Dated November 4, 2025 and Prospectus Dated January 27, 2025)

SERIES A PERPETUAL STRIDE PREFERRED STOCK ANNEX

10.00% Series A Perpetual Stride Preferred Stock

We have entered into an Omnibus Sales Agreement (the "Sales Agreement") with TD Securities (USA) LLC, Barclays Capital Inc., The Benchmark Company, LLC, BTIG, LLC, Canaccord Genuity LLC, Cantor Fitzgerald & Co., Clear Street LLC, Compass Point Research & Trading, LLC, H.C. Wainwright & Co., LLC, Keefe, Bruyette & Woods, Inc., Maxim Group LLC, Mizuho Securities USA LLC, Morgan Stanley & Co. LLC, Santander US Capital Markets LLC, SG Americas Securities, LLC, and TCBI Securities Inc. doing business as Texas Capital Securities (collectively, the "Agents"), dated November 4, 2025, relating to the sale of shares of our class A common stock, par value $0.001 per share, and shares of several series of our preferred stock, par value $0.001 per share. In accordance with the terms of the Sales Agreement, under this prospectus supplement, relating to the sale of our 10.00% Series A Perpetual Stride Preferred Stock (the "STRD Stock Annex"), we may offer and sell shares of our 10.00% Series A Perpetual Stride Preferred Stock ("STRD Stock"), having an aggregate offering price of up to $4,133,799,112.67 from time to time through one or more of the Agents, acting as our sales agents. The shares of STRD Stock offered hereunder are among the securities described in the base prospectus supplement dated November 4, 2025 that we filed with the Securities and Exchange Commission on such date (the "base prospectus supplement") and an accompanying prospectus dated January 27, 2025. This STRD Stock Annex should be read in conjunction with that base prospectus supplement and accompanying prospectus and the contents of that base prospectus supplement and accompanying prospectus are incorporated by reference into this Common Stock Annex.

We had previously registered the offer issuance and sale of up to $4,200,000,000 of our STRD Stock under a prospectus supplement dated July 7, 2025. Prior to the date of this STRD Stock Annex, we have previously sold 774,983 shares of STRD Stock under such prior prospectus supplement for gross proceeds of $66.2 million, with shares of STRD Stock with an aggregate offering price of up to $4,133,799,112.67 remaining unsold under such offering. As of the date of this STRD Stock Annex, we have terminated such prior offering of STRD Stock and the sales agreement relating to such prior offering and such unsold shares of STRD Stock will no longer be offered and sold under the prior prospectus supplement. Instead, the remaining $4,133,799,112.67 of our STRD Stock will be offered and sold under this STRD Stock Annex, the accompanying base prospectus supplement dated November 4, 2025 and the accompanying prospectus.

Our STRD Stock is listed on The Nasdaq Global Select Market under the trading symbol "STRD." On November 3, 2025, the last reported sale price of our STRD Stock as reported on The Nasdaq Global Select Market was $78.14 per share.

STRD STOCK

The up to $4,133,799,112.67 of shares of STRD Stock that we may offer and sell under this STRD Stock Annex and the accompanying base prospectus supplement and prospectus constitutes a further issuance of shares of STRD Stock in addition to the 12,539,683 shares of STRD Stock outstanding as of the date of this STRD Stock Annex. Other than the issue date, the first regular dividend record date and first regular dividend payment date, STRD Stock that we may offer and sell under this STRD Stock Annex and the accompanying base prospectus supplement and prospectus will have terms identical to, will have the same CUSIP number as, and will vote together with, the STRD Stock outstanding as of the date of this STRD Stock Annex immediately upon issuance.

The STRD Stock has an initial liquidation preference of $100 per share. The liquidation preference is subject to adjustment in the manner described in this STRD Stock Annex. However, the liquidation preference will not be adjusted to an amount that is less than $100 per share.

Dividends on shares of the STRD Stock are not mandatory. Holders of the STRD Stock will be entitled to receive non-cumulative dividends, which we refer to as "regular dividends," at a rate per annum equal to 10.00% on the stated amount thereof, which is $100 per share of STRD Stock, out of funds legally available for their payment only when, as, and if declared by our board of directors or any duly authorized committee thereof. If declared, regular dividends on the STRD Stock will be payable quarterly in arrears on March 31, June 30, September 30 and December 31 of each year. Since regular dividends are not cumulative, we do not have any obligation to pay any regular dividend for any regular dividend period unless we declare such regular dividend prior to the regular dividend payment date for such regular dividend period. No dividend, interest or other amount will accumulate or accrue on any unpaid regular dividends, regardless of whether regular dividends are declared for any future regular dividend period. Declared regular dividends on the STRD Stock will be payable solely in cash in the manner, and subject to the provisions, described in this STRD Stock Annex.

We have the right, at our election, to redeem all, and not less than all, of the STRD Stock, at any time, for cash if the total number of shares of all STRD Stock then outstanding is less than 25% of the total number of shares of STRD Stock originally issued in this initial offering and in any future offering taken together. In addition, we have the right to redeem all, but not less than all, of the STRD Stock if a "tax event" (as defined in this STRD Stock Annex) occurs. The redemption price for any STRD Stock to be redeemed will be a cash amount equal to the liquidation preference of the STRD Stock to be redeemed as of the business day before the date we send the related redemption notice, plus declared and unpaid regular dividends, if any, that will have accrued to, but excluding, the redemption date. For the avoidance of doubt, the redemption price will not include payment of any undeclared regular dividends.

If a "fundamental change" (as defined in this STRD Stock Annex) occurs, then, except as described in this STRD Stock Annex, holders of STRD Stock will have the right (which we refer to as the "fundamental change repurchase right") to require us to repurchase some or all of their shares of STRD Stock at a cash repurchase price equal to the stated amount of the STRD Stock to be repurchased, plus declared and unpaid regular dividends, if any, that will have accrued to, but excluding the fundamental change repurchase date. For the avoidance of doubt, the fundamental change repurchase price will not include payment of any undeclared regular dividends.

Our business and an investment in the STRD Stock involve significant risks. These risks are described under the caption "Risk Factors" beginning on page SA-6 of this STRD Stock Annex, under the caption "Risk Factors", "Risk Factors Related to the ATM Offering Programs" and "Risk Factor Updates" in the accompanying base prospectus supplement dated November 4, 2025 and prospectus and in the documents incorporated by reference into the accompanying prospectus supplement dated November 4, 2025 and prospectus.

Neither the Securities and Exchange Commission nor any state or foreign securities commission or regulatory authority has approved or disapproved of these securities or passed upon the adequacy or accuracy of this STRD Stock Annex, the accompanying base prospectus supplement dated November 4, 2025 or the prospectus. Any representation to the contrary is a criminal offense.

We expect to deliver the STRD Stock in book-entry form only through the facilities of The Depository Trust Company on or about the next trading day following the date of purchase.

November 4, 2025

ADDITIONAL DOCUMENTS RELATED TO THE OFFERING

You should read this STRD Stock Annex in conjunction with the base prospectus supplement dated November 4, 2025 and the accompanying prospectus dated January 27, 2025. This STRD Stock Annex contains the specific terms of the STRD Stock and of our at-the-market offering of up to $4,133,799,112.67 of shares our of STRD Stock and the base prospectus supplement describes the terms applicable to our at-the-market offerings of class A common stock and preferred stock in general. You should carefully consider, among other things, the matters set forth under "Risk Factors Related to the ATM Offering Programs" in the base prospectus supplement and "Risk Factors" in this STRD Stock Annex.

You may access the base prospectus supplement and accompanying prospectus on the SEC website at https://www.sec.gov as follows (or if such address has changed, by reviewing our filings for the relevant date on the SEC website): https://www.sec.gov/Archives/edgar/data/1050446/000119312525263653/d87896d424b2.htm

TABLE OF CONTENTS

PROSPECTUS SUPPLEMENT

STRD STOCK ANNEX

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RISK FACTORS

An investment in the STRD Stock involves a high degree of risk. Before deciding whether to invest in the STRD Stock, you should carefully consider the risks described below and discussed under the sections captioned "Risk Factors", "Risk Factors Related to the ATM Offering Programs" and "Risk Factor Updates" contained in the accompanying base prospectus supplement and prospectus and in our most recent Annual Report on Form 10-K, any of our subsequent Quarterly Reports on Form 10-Q, and any of our Current Reports on Form 8-K that are incorporated by reference herein, together with other information in this STRD Stock Annex, in the accompanying base prospectus supplement and prospectus, and in any free writing prospectus that we have authorized for use in connection with this offering. If any of these risks actually occurs, our business, financial condition, results of operations or cash flow could be seriously harmed, resulting in a loss of all or part of your investment. As used in this section, (i) "we," "our" and "us" refer to Strategy Inc and not to its subsidiaries; and (ii) "preferred stockholder" refers to a registered holder of the STRD Stock.

Risks Related to the STRD Stock and This Offering

Although the STRD Stock is senior to our class A common stock and class B common stock, it is junior to our STRF Stock, our STRC Stock, our STRK Stock, our existing and future indebtedness, structurally junior to the liabilities of our subsidiaries and subject to the rights and preferences of any other series of preferred stock then outstanding.

If we liquidate, dissolve or wind up, whether voluntarily or involuntarily, then our assets will be available to distribute to our equity holders, including holders of the STRD Stock, only if all of our then outstanding indebtedness is first paid in full. The remaining assets, if any, would then be allocated among the holders of our equity securities in accordance with their respective liquidation rights. Since our STRF Stock, our STRC Stock and our STRK Stock is liquidation senior stock, we would be required to pay the amounts due upon such liquidation senior stock in full before making any payments on the STRD Stock. If we issue any additional liquidation senior stock in the future, then we would also be required to pay the amounts due upon such additional liquidation senior stock in full before making any payments on the STRD Stock. If any assets remain after any liquidation senior stock is paid in full, those assets will be distributed pro rata among holders of the STRD Stock and any other liquidation parity stock then outstanding. There may be insufficient remaining assets available to pay the liquidation preference and any declared and unpaid dividends, if any, that have accrued on the STRD Stock. As of September 30, 2025, excluding intercompany indebtedness, we had approximately $8.24 billion in aggregate principal amount of consolidated indebtedness outstanding. Additionally, as of October 31, 2025, there were 12,470,812 shares of STRF Stock outstanding, 28,011,111 shares of STRC Stock outstanding, 13,918,518 shares of STRK Stock outstanding, and no dividend parity stock or liquidation parity stock outstanding. Our indebtedness, STRF Stock, STRC Stock and STRK Stock rank senior to the STRD Stock. As of October 31, 2025, there were 267,713,485 shares of class A common stock outstanding and 19,640,250 shares of class B common stock outstanding, all of which rank junior to the STRD Stock.

In addition, our subsidiaries have no obligation to pay any amounts on the STRD Stock. If any of our subsidiaries liquidates, dissolves or winds up, whether voluntarily or involuntarily, then we, as a direct or indirect common equity owner of that subsidiary, will be subject to the prior claims of that subsidiary's creditors, including trade creditors and preferred equity holders. We may never receive any amounts from that subsidiary, and, accordingly, the assets of that subsidiary may never be available to make payments on the STRD Stock.

We may not have sufficient funds to pay dividends in cash on the STRD Stock, or we may choose not to declare or pay dividends on the STRD Stock. In addition, regulatory and contractual restrictions may prevent us from declaring or paying dividends.

We expect to fund any dividends paid in cash on the STRD Stock primarily through additional capital raising activities, including, but not limited to, at-the-market offerings of our class A common stock. However, our

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ability to declare and pay cash dividends on the STRD Stock will depend on many factors, including the following:

In addition, our board of directors or any duly authorized committee thereof may choose not to declare or pay accrued dividends, or to declare and pay less than the full amount of dividends, on the STRD Stock for any reason, even if we have sufficient funds to declare and pay accrued dividends on the STRD Stock in full. In addition, if we fail to declare and pay accrued dividends on the STRD Stock in full, then the value of the STRD Stock will likely decline.

Provisions contained in the instruments governing our future indebtedness may restrict or prohibit us from paying cash dividends on the STRD Stock. If the terms of our indebtedness restrict or prohibit us from paying dividends, then we may seek to refinance that indebtedness or seek a waiver that would permit the payment of dividends. However, we may be unable or may choose not to refinance the indebtedness or obtain a waiver.

Under the Delaware General Corporation Law, we may declare dividends on the STRD Stock only out of our "surplus" (which generally means our total assets less total liabilities, each measured at their fair market values, less statutory capital), or, if there is no surplus, out of our net profits for the current or the immediately preceding fiscal year. We may not have sufficient surplus or net profits to declare and pay dividends on the STRD Stock in cash.

If we fail to declare and pay full dividends on our STRK Stock, our STRC Stock and our STRF Stock, we will be prohibited from paying dividends on the STRD Stock. Moreover, if we fail to declare and pay full dividends on the STRD Stock, then we will be prohibited from paying dividends on our class A common stock and any other junior securities, subject to limited exceptions. Further, no dividends may be declared or paid on any class or series of dividend parity stock unless regular dividends are simultaneously declared on the STRD Stock on a pro rata basis (as described further under the caption "Description of STRD Stock -Regular Dividends-Priority of Dividends; Limitation on Junior Payments; No Participation Rights- Limitation on Dividends on Parity Stock").

You may not receive dividends on the STRD Stock, which are discretionary and non-cumulative.

Regular dividends on the STRD Stock are discretionary and will not be cumulative. If our board of directors or any duly authorized committee thereof does not declare a regular dividend on the STRD Stock in respect of a regular dividend period, then no regular dividend will be deemed to have accrued for such regular dividend

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period, be payable on the applicable regular dividend payment date or be cumulative, and we will have no obligation to pay any regular dividend for that regular dividend period, whether or not our board of directors or any duly authorized committee thereof declares a regular dividend on the STRD Stock, any other series of our preferred stock or our common stock for any future dividend period. Accordingly, you may not receive regular dividends on the STRD Stock.

The STRD Stock has only limited voting rights.

The STRD Stock confers no voting rights except with respect to certain amendments to the terms of the STRD Stock, and certain other limited circumstances described in this STRD Stock Annex and except as required by the Delaware General Corporation Law. Holding STRD Stock will not confer the right to vote together with holders of our class A common stock on matters on which our class A common stockholders are entitled to vote. For example, holders of STRD Stock, as such, do not have the right to vote in the general election of our directors and do not have any additional voting rights upon non-payment of regular dividends such as the right to elect any directors to our board of directors. Accordingly, the voting provisions of the STRD Stock may not afford you meaningful protections for your investment.

Without the consent of any holder of our STRD Stock, we may issue preferred stock in the future that ranks equally with or senior to the STRD Stock with respect to dividends and liquidation rights, which may adversely affect the rights of preferred stockholders.

Without the consent of any holder of STRD Stock, we may authorize and issue preferred stock (including additional STRD Stock) that ranks equally with or senior to the STRD Stock with respect to the payment of dividends or the distribution of assets upon our liquidation, dissolution or winding up. If we issue any such equally ranked preferred stock in the future, the rights of holders of the STRD Stock will be diluted and the trading price of the STRD Stock may decline. For example, if we issue any dividend senior stock in the future (including additional STRK Stock or STRF Stock), such dividend senior stock could contain (or, in the case of our STRK Stock and STRF Stock, contain) provisions that prohibit us from paying dividends on the STRD Stock or purchasing, redeeming or acquiring the STRD Stock until and unless we first pay accumulated dividends in full on such dividend senior stock.

A liquid trading market for the STRD Stock may not be maintained.

Although we have listed the STRD Stock on The Nasdaq Global Select Market, a liquid trading market for the STRD Stock may not continue to develop or be maintained, and the listing may be subsequently withdrawn. Accordingly, you may not be able to sell your STRD Stock at the times you wish to or at favorable prices, if at all.

The liquidity of the trading market, if any, and future trading prices of the STRD Stock will depend on many factors, including, among other things, 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.

Market volatility could significantly harm the market for the STRD Stock, regardless of our financial condition, results of operations, business, prospects or credit quality.

The condition of the financial markets, prevailing interest rates and other factors could significantly affect the trading price of the STRD Stock.

The condition of the financial markets and changes in prevailing interest rates can have an adverse effect on the trading price of the STRD Stock. 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 STRD Stock. 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 STRD Stock to fall significantly.

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Holders of STRD Stock may be treated as receiving deemed distributions, and consequently may be subject to tax with respect to the STRD Stock under certain circumstances, even though no corresponding distribution of cash has been made.

Under Section 305 of the Internal Revenue Code of 1986, as amended (the "Code"), holders of STRD Stock may be treated as receiving a deemed distribution on the STRD Stock under certain circumstances, including (i) an increase in the liquidation preference of the STRD Stock or (ii) if the STRD Stock is issued at a discount. The liquidation preference of the STRD Stock is subject to adjustment in the manner described in this STRD Stock Annex, which adjustment may result in an increase in the liquidation preference. Such increase in the liquidation preference could give rise to a deemed dividend to holders of STRD Stock. Although the matter is not entirely clear, we believe any such adjustment of liquidation preference in the manner described in this STRD Stock Annex or discount should not be treated as giving rise to a deemed distribution on the STRD Stock. However, there is no assurance that the Internal Revenue Service (the "IRS") or an applicable withholding agent will not take a contrary position.

Any deemed distribution will generally be taxable to the same extent as a cash distribution. In addition, for any STRD stockholder that is a "non-U.S. holder" (as defined in "Material United States Federal Income Tax Considerations"), any deemed distribution could be subject to U.S. federal withholding tax at a 30% rate, or such lower rate as may be specified by an applicable treaty. Because deemed distributions received by a holder of STRD Stock would not give rise to any cash from which any applicable withholding tax could be satisfied, if we (or an applicable withholding agent) pay withholding (including backup withholding) on behalf of a holder of STRD Stock, we (or an applicable withholding agent) may set off any such payment against, or withhold such taxes from, payments of cash to such holder of STRD Stock or sales proceeds received by, or other funds or assets of, such holder of STRD Stock, or require alternative arrangements with respect to such withholding taxes.

The application of the rules under Section 305 of the Code to the STRD Stock is uncertain, and holders of STRD Stock should consult their tax advisors about the impact of these rules in their particular situations.

Holders of STRD Stock may not be entitled to the dividends-received deduction or preferential tax rates applicable to qualified dividend income.

Distributions paid to corporate U.S. holders may be eligible for the dividends-received deduction and distributions paid to non-corporate U.S. holders may be subject to tax at the preferential tax rates applicable to "qualified dividend income" if we have current or accumulated earnings and profits, as determined for U.S. federal income tax purposes and certain holding period and other requirements are met. We do not have any accumulated earnings and profits, and do not expect to generate current earnings and profits in the current year or the foreseeable future. Accordingly, the distributions on the STRD Stock are generally not expected to qualify as dividends for U.S. federal income tax purposes in the current year or the foreseeable future.

We intend to provide public notice to the holders of STRD Stock to the extent that the distributions on STRD Stock are not treated as being made out of our current or accumulated earnings and profits. For the avoidance of doubt, our expectation on earnings and profits could change, therefore the U.S. federal income tax treatment of the distributions on STRD Stock could change. Holders of STRD Stock are encouraged to consult with their tax advisors regarding the implications of our current or accumulated earnings and profits for U.S. federal income tax purposes.

The tax rules applicable to "fast-pay stock" could result in adverse consequences to holders of STRD Stock.

Under Treasury Regulations promulgated under Section 7701(l) of the Code (the "Fast-Pay Stock Regulations"), if stock of a corporation is structured such that dividends paid with respect to the stock are economically (in whole or in part) a return of the stockholder's investment (rather than a return on the stockholder's investment), then the stock is characterized as "fast-pay stock" and is subject to adverse tax reporting requirements and

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potentially penalties, as described below. In addition, under the Fast-Pay Stock Regulations, unless clearly demonstrated otherwise, stock is presumed to be fast-pay stock if it is structured to have a dividend that is reasonably expected to decline (as opposed to a dividend rate that is reasonably expected to fluctuate or remain constant) (for such purpose, the dividend rate may be viewed as reasonably expected to decline if we are reasonably expected to stop paying regular dividends on the STRD Stock) or is issued for an amount that exceeds (by more than a de minimis amount, as determined under applicable Treasury Regulations) the amount at which the stockholder can be compelled to dispose of the stock. It is not clear what amount would constitute "de minimis" in the case of stock with a perpetual term.

The determination of whether stock is fast-pay stock is based on all the facts and circumstances. To determine if it is fast-pay stock, stock is examined when issued, and, for stock that is not fast-pay stock when issued, when there is a significant modification in the terms of the stock or the related agreements or a significant change in the relevant facts and circumstances. The relevant tax regulations do not indicate the types of significant changes in facts and circumstances that are intended to give rise to such a determination.

We may issue shares of STRD Stock from time to time under this STRD Stock Annex (the "Offered Shares") and may otherwise issue shares of STRD Stock (or resell any shares that we or any of our subsidiaries have purchased or otherwise acquired) from time to time (such issued or resold shares, the "Additional Shares"). We do not intend to issue any shares of STRD Stock that would be treated as fast-pay stock, and we do not believe that we structured any Offered Shares, or will structure any Additional Shares, such that dividends paid by us with respect to the STRD Stock will be economically a return of a stockholder's investment. Moreover, we have obtained, and we intend to obtain in the future, advice of counsel in connection with offerings of STRD Stock for the purpose of analyzing the consequences of issuing such shares, including in light of any legal developments regarding the definition of fast-pay stock. As the liquidation preference of the STRD Stock is subject to adjustment in the manner described in this STRD Stock Annex, it is generally not expected that any Offered Shares or Additional Shares would be issued at such a level of premium above their liquidation preference at the time of sale of the Offered Shares or Additional Shares so as to implicate the fast-pay stock rules. Nonetheless, there may be increased risk that the IRS could assert that such Offered Shares or Additional Shares constitute fast-pay stock.

Transactions involving fast-pay stock arrangements are treated as "listed transactions" for U.S. federal income tax purposes. Issuers and holders of any shares of fast-pay stock would be required to report their participation in the transaction on IRS Form 8886 on an annual basis with their U.S. federal income tax returns and would also be required to mail a copy of that form to the IRS Office of Tax Shelter Analysis. Failure to comply with those disclosure requirements could result in the assessment by the IRS of interest, additions to tax and onerous penalties. In addition, an accuracy-related penalty applies under the Code to any reportable transaction understatement attributable to a listed transaction if a significant purpose of the transaction is the avoidance or evasion of U.S. federal income tax. Furthermore, certain material advisors would also be required to file a disclosure statement with the IRS. If we determine that we are required to file an IRS Form 8886 (including a protective filing) in connection with the potential issuance of fast-pay stock with respect to any STRD Stock, we intend to provide public notice to the applicable holders of the STRD Stock, which notice may be by a press release, by publication on our investor relations website, or by filing a current report on Form 8-K with the SEC.

Notwithstanding our intent not to issue STRD Stock that would be fast-pay stock, the rules regarding the definition of fast-pay stock are unclear in certain respects and, therefore, the IRS could disagree with our determination and treat Offered Shares or Additional Shares as fast-pay stock. In addition, even if a particular issuance of Offered Shares or Additional Shares is not fast-pay stock, the treatment of any other shares of STRD Stock-including other Offered Shares or any Additional Shares-as fast-pay stock (for example, as a result of a determination by the IRS) could result in adverse consequences to holders of all shares of STRD Stock because the shares may be indistinguishable from each other. See "-An issuance of STRD Stock could have an adverse tax profile, which could subject holders of any other shares of STRD Stock to adverse consequences" below.

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Accordingly, holders of STRD Stock are strongly urged to consult their tax advisors regarding the Fast-Pay Stock Regulations and their potential consequences to an investment in the STRD Stock.

An issuance of STRD Stock could have an adverse tax profile, which could subject holders of any other shares of STRD Stock to adverse consequences.

If we issue shares of STRD Stock-whether Offered Shares or Additional Shares-that have a different, and potentially adverse, tax profile or treatment for U.S. federal income tax purposes from your shares of STRD Stock, since all such shares would trade under the same CUSIP or other identifying number, your shares of STRD Stock may be treated by subsequent purchasers, withholding agents and potentially the IRS as having the same adverse tax profile or treatment if they are not otherwise distinguishable from the STRD Stock subject to such adverse treatment.

For example, notwithstanding our intent not to issue any shares of STRD Stock that are fast-pay stock, the IRS could assert that certain shares of STRD Stock constitute fast-pay stock. See "-The tax rules applicable to "fast-pay stock" could result in adverse consequences to holders of STRD Stock" above.

Furthermore, if any shares of STRD Stock are issued at a price that exceeds their liquidation preference, such shares would constitute "disqualified preferred stock" within the meaning of Section 1059(f)(2) of the Code and any corporate U.S. holder generally will be required to reduce its tax basis (but not below zero) in the STRD Stock by the amount of any dividends-received deduction it receives. The liquidation preference of the STRD Stock is subject to adjustment in the manner described in this STRD Stock Annex, which adjustment may be taken into account for purposes of disqualified preferred stock determination. If any shares of STRD Stock issued are considered disqualified preferred stock, the other shares of STRD Stock could also be subject to the same treatment as a practical matter due to fungible trading.

If any shares of STRD Stock are sold at a discount, such shares may be subject to rules that require the accrual of such discount (or a greater discount than the discount that applies to any other shares of STRD Stock) currently over the deemed term of the shares as deemed distributions under U.S. tax rules similar to those governing original issue discount for debt instruments. In that event, the IRS or a withholding agent may treat any such discount as resulting in deemed taxable distributions with respect to all shares of STRD Stock, including those not issued at a discount (or issued at a lesser discount).

Because the IRS or other parties (such as withholding agents) may not be able to distinguish the shares of STRD Stock offered or resold from time to time, a holder of STRD Stock might be subject to adverse tax consequences or might be required to demonstrate to the IRS (or such other parties) that the holder purchased the STRD Stock in a specific offering to which those adverse tax consequences did not apply. Moreover, any adverse tax consequences as described above in connection with the issuance of any Offered Shares or Additional Shares may adversely affect the trading price of the STRD Stock. See "Material United States Federal Income Tax Considerations" for further discussion.

Provisions of the STRD Stock could delay or prevent an otherwise beneficial takeover of us.

Certain provisions in the STRD Stock 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 STRD Stock Annex, preferred stockholders will have the right to require us to repurchase their STRD Stock for cash. See "Description of STRD Stock -Fundamental Change Permits Preferred Stockholders to Require Us to Repurchase STRD Stock." These fundamental change provisions could increase the cost of acquiring us or otherwise discourage a third party from acquiring us or removing incumbent management, including in a transaction that preferred stockholders may view as favorable.

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Your investment in the STRD Stock may be harmed if we redeem the STRD Stock.

We have the right to redeem the STRD Stock in certain circumstances. See "Description of STRD Stock-Redemption at Our Option." If we redeem your STRD Stock, then you may be unable to reinvest any proceeds from the redemption in comparable investments at favorable dividend or interest rates.

Because the STRD Stock is held in book-entry form, holders of the STRD Stock must rely on DTC's procedures to exercise their rights and remedies.

We initially issued the STRD Stock, and the STRD Stock sold in this offering will be initially issued, in the form of "global certificates" registered in the name of Cede & Co., as nominee of DTC. Beneficial interests in global certificates are shown on, and transfers of global certificates are effected only through, the records maintained by DTC. Except in limited circumstances, we will not issue physical certificates representing the STRD Stock. See "Description of STRD Stock -Book Entry, Settlement and Clearance." Accordingly, if you own a beneficial interest in a global certificate, then you will not be considered an owner or holder of the STRD Stock. Instead, DTC or its nominee will be the sole holder of the STRD Stock. Payments of cash dividends and other cash amounts on global certificates 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 certificates and that those participants will credit the payments to indirect DTC participants. Unlike persons who have physical certificates registered in their names, owners of beneficial interests in global certificates will not have the direct right to act on our solicitations for consents or requests for waivers or other actions from holders of the STRD Stock. 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 certificates to vote on any requested actions on a timely basis.

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USE OF PROCEEDS

From time to time, we may issue and sell shares of our STRD Stock having aggregate sales proceeds of up to $4,133,799,112.67. Because there is no minimum offering amount required as a condition to effect this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time.

We intend to use the net proceeds from this offering for general corporate purposes, including the acquisition of bitcoin and for working capital, and may also use the net proceeds for the payment of cash dividends declared from time to time on shares of any dividend senior stock then outstanding.

Bitcoin is a highly volatile asset that has traded below $70,000 per bitcoin and above $120,000 per bitcoin in our principal market in the 12 months preceding the date of this STRD Stock Annex. Bitcoin does not pay interest or other returns and so our ability to generate cash from our bitcoin holdings depends on sales. Future fluctuations in bitcoin trading prices may result in our converting bitcoin purchased with the net proceeds from this offering into cash with a value substantially below the net proceeds from this offering, and there can be no assurance as to whether or when we will realize any cash proceeds from our contemplated acquisition of bitcoin.

We have not determined the amount of net proceeds to be used specifically for any of these purposes. As a result, our management will have broad discretion in the application of the net proceeds from this offering and you will not have the opportunity as part of your investment decision to assess whether the net proceeds are being used in a manner of which you approve.

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DESCRIPTION OF STRD STOCK

The following is a summary of certain provisions of the STRD Stock. It is only a summary and is not complete. The terms of our STRD Stock are set forth in a certificate of designations (the "certificate of designations") and our second restated certificate of incorporation (as amended and supplemented to date, the "certificate of incorporation"). We qualify this summary by referring you to the certificate of designations and our certificate of incorporation, because they, and not this summary, define your rights as a holder of the STRD Stock. We will provide you, upon written request, with a copy of the certificate of designations, which includes the form of the certificates that will represent the STRD Stock, and our certificate of incorporation, as provided under the caption "Where You Can Find Additional Information; Incorporation by Reference" in the accompanying base prospectus supplement.

Certain terms used in this summary are defined below under the caption "-Definitions." Certain other terms used in this summary are defined in the certificate of designations.

References to "we," "us" and "our" in this section refer to Strategy Inc only and not to any of its subsidiaries.

This "Description of STRD Stock" section supplements and, to the extent inconsistent therewith, supersedes the information in the accompanying prospectus under the caption "Description of Capital Stock."

General

Our certificate of incorporation authorizes us to issue up to 1,005,000,000 shares of preferred stock, $0.001 par value per share, in one or more series, and authorizes our board of directors to designate the preferences, rights and other terms of each series. Our board of directors has authorized the issuance of up to 33,200,000 shares of STRF Stock, 70,435,000 shares of STRC Stock, 269,800,000 shares of STRK Stock and 61,176,000 shares of STRD Stock. As of October 31, 2025, 12,539,683 shares of STRD Stock, 12,470,812 shares of STRF Stock, 28,011,111 shares of STRC Stock and 13,918,518 shares of STRK Stock were outstanding.

The up to $4,133,799,112.67 of shares of STRD Stock that we may offer and sell under this STRD Stock Annex and the accompanying base prospectus supplement and prospectus constitutes a further issuance of shares of STRD Stock in addition to the 12,539,683 shares of STRD Stock outstanding as of the date of this STRD Stock Annex. Other than the issue date, the first regular dividend record date and the first regular dividend payment date, the STRD Stock that we may offer and sell under this STRD Stock Annex and the accompanying base prospectus supplement and prospectus will have terms identical to, will have the same CUSIP number as, and will vote together with, the STRD Stock outstanding as of the date of this STRD Stock Annex immediately upon issuance.

Without the consent of any holder, we may, by resolution of our board of directors, increase the total number of authorized shares of STRD Stock, except that in no event will such increase be by an amount that exceeds the total number of authorized and undesignated shares of our preferred stock. In addition, without the consent of any holder of STRD Stock, we may issue additional STRD Stock with the same terms as the STRD Stock we are offering (except for certain differences, such as the date as of which regular dividends begin to accrue on, the first regular dividend record date and first regular dividend payment date for, and transfer restrictions applicable to, such additional STRD Stock). Furthermore, without the consent of any holder, we may resell any STRD Stock that we or any of our "subsidiaries" (as defined below under the caption "-Definitions") has purchased or otherwise acquired. However, such additional or resold STRD Stock must be identified by a separate CUSIP number or by no CUSIP number if they are not fungible, for purposes of federal securities laws or, if applicable, the "depositary procedures" (as defined below under the caption "-Definitions"), with other STRD Stock that is then outstanding. In addition, without the consent of any holder, we may create and issue, or increase the authorized or issued number of, any other class or series of stock (including, for the avoidance of doubt,

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"dividend senior stock," "dividend parity stock," "liquidation senior stock" or "liquidation parity stock" (as those terms are defined below under the caption "-Definitions")), including our STRF Stock, our STRC Stock and our STRK Stock.

Subject to applicable law, we or our subsidiaries may directly or indirectly repurchase STRD Stock in the open market or otherwise, whether through private or public tender or exchange offers, cash-settled swaps or other cash-settled derivatives.

Transfer Agent, Registrar and Paying Agent

U.S. Bank Trust Company, National Association is the initial transfer agent, registrar and paying agent for the STRD Stock. However, without prior notice to the preferred stockholders, we may change the transfer agent, registrar and paying agent and we or any of our subsidiaries may choose to act in that capacity as well (except that the transfer agent, registrar and paying agent with respect to any global certificate must at all times be a person that is eligible to act in that capacity under the depositary procedures).

Registered Holders

Absent manifest error, a person in whose name any share of STRD Stock is registered on the registrar's books will be considered to be the holder of that share for all purposes, and only registered holders (which, in the case of STRD Stock held through DTC, will initially be DTC's nominee, Cede & Co.) will have rights under our certificate of incorporation and certificate of designations as holders of the STRD Stock. In this section, we refer to the registered holders of the STRD Stock as "holders" of the STRD Stock or "preferred stockholders."

The STRD Stock will be initially issued in global form, represented by one or more "global certificates" registered in the name of Cede & Co., as nominee of DTC, and DTC will act as the initial depositary for the STRD Stock. In limited circumstances, global certificates will be exchanged for "physical certificates" registered in the name of the applicable preferred stockholders. See "-Book Entry, Settlement and Clearance" for a definition of these terms and a description of certain DTC procedures that will be applicable to STRD Stock represented by global certificates.

Transfers and Exchanges

A preferred stockholder may transfer or exchange its STRD Stock at the office of the registrar in accordance with the certificate of designations. We, the transfer agent and the registrar may require the preferred stockholder to, among other things, deliver appropriate endorsements or transfer instruments as we or they may reasonably require. In addition, subject to the terms of the certificate of designations, we, the transfer agent and the registrar may refuse to register the transfer or exchange of any share of STRD Stock that is subject to redemption or required repurchase.

Listing

The STRD Stock is listed on The Nasdaq Global Select Market under the symbol "STRD."

Payments on the STRD Stock

We will pay (or cause our paying agent to pay) all declared cash regular dividends or other cash amounts due on any STRD Stock represented by a global certificate by wire transfer of immediately available funds. We will pay (or cause our paying agent to pay) all declared cash regular dividends or other cash amounts due on any STRD Stock represented by a physical certificate as follows:

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To be timely, a written request referred to in the first bullet point above must be delivered no later than the "close of business" (as defined below under the caption "-Definitions") on the following date: (i) with respect to the payment of any declared cash regular dividend due on a regular dividend payment date for the STRD Stock, 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 any STRD Stock is not a "business day" (as defined below under the caption "-Definitions"), 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, dividend or other amount will accrue or accumulate 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 "business day."

Ranking

The STRD Stock ranks as follows:

The terms of the STRD Stock will not restrict us from issuing dividend senior stock, dividend parity stock, liquidation senior stock or liquidation parity stock.

As of September 30, 2025, excluding intercompany indebtedness, we had approximately $8.24 billion in aggregate principal amount of consolidated indebtedness outstanding. Additionally, as of October 31, 2025, there were 12,470,812 shares of STRF Stock outstanding, 28,011,111 shares of STRC Stock outstanding, 13,918,518 shares of STRK Stock outstanding, and no dividend parity stock or liquidation parity stock outstanding. Our indebtedness, STRF Stock outstanding, STRC Stock outstanding and STRK Stock outstanding rank senior to the STRD Stock outstanding.

Regular Dividends

Generally

Holders of the STRD Stock will be entitled to receive non-cumulative dividends (which we refer to as "regular dividends") at a rate per annum equal to 10.00% (such rate per annum, the "regular dividend rate") on the "stated

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amount" (as defined below under the caption "-Definitions") thereof, out of funds legally available for their payment, and subject to the other provisions described below, only when, as, and if declared by our "board of directors" (as defined below under the caption "-Definitions"). If declared, regular dividends will be payable quarterly in arrears on each "regular dividend payment date" (as defined below under the caption "-Definitions") to the preferred stockholders of record as of the close of business on the "regular record date" (as defined below under the caption "-Definitions") immediately preceding the applicable regular dividend payment date. Since regular dividends are not cumulative, we will not have any obligation to pay any regular dividend for any regular dividend period unless we declare such regular dividend prior to the regular dividend payment date for such regular dividend period. No dividend, interest or other amount will accumulate or accrue on any unpaid regular dividends, regardless of whether regular dividends are declared for any future regular dividend period.

Regular dividends on the STRD Stock will accrue from, and including, the last regular dividend payment date (or, in the case of the first regular dividend period, from, and including, June 10, 2025), to, but excluding, the next regular dividend payment date (in each case, regardless of whether regular dividends were declared or paid in respect of any prior regular dividend period).

Declared regular dividends on the STRD Stock will be payable solely in cash in the manner, and subject to the provisions, described below under the caption "-Method of Payment."

Accrued regular dividends will be computed on the basis of a 360-day year comprised of twelve 30-day months.

The certificate of designations does not require us to declare regular dividends on the STRD Stock, even if funds are legally available for their payment. Accordingly, we may choose not to declare regular dividends on the STRD Stock. See "Risk Factors-Risks Related to the STRD Stock and This Offering-We may not have sufficient funds to pay dividends in cash on the STRD Stock, or we may choose not to declare or pay dividends on the STRD Stock. In addition, regulatory and contractual restrictions may prevent us from declaring or paying dividends."

Method of Payment

Each declared regular dividend on the STRD Stock will be paid in cash.

Treatment of Dividends Upon Repurchase Upon Fundamental Change or Redemption

If the "fundamental change repurchase date" (as defined below under the caption "-Fundamental Change Permits Preferred Stockholders to Require Us to Repurchase STRD Stock"), or redemption date of any share of STRD Stock to be repurchased or redeemed is after a regular record date for a declared regular dividend on the STRD Stock and on or before the next regular dividend payment date, then the holder of such share at the close of business on such regular record date will be entitled, notwithstanding such repurchase or redemption, as applicable, to receive, on or, at our election, before such regular dividend payment date, such declared regular dividend on such share.

Except as described in the preceding paragraph, regular dividends on any share of STRD Stock will cease to accrue from and after the fundamental change repurchase date or redemption date, as applicable, for such share.

Limitations on Our Ability to Pay Dividends

We may not have sufficient cash to pay regular dividends on the STRD Stock in cash. In addition, applicable law (including the Delaware General Corporation Law), regulatory authorities, the agreements governing our indebtedness and our dividend senior stock, including our STRK Stock and our STRF Stock, may restrict our ability to pay dividends on the STRD Stock. Similarly, statutory, contractual or other restrictions may limit our subsidiaries' ability to pay dividends or make distributions, loans or advances to us to enable us to pay regular

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dividends on the STRD Stock. See "Risk Factors-Risks Related to the STRD Stock and This Offering-We may not have sufficient funds to pay dividends in cash on the STRD Stock, or we may choose not to declare or pay dividends on the STRD Stock. In addition, regulatory and contractual restrictions may prevent us from declaring or paying dividends."

Priority of Dividends; Limitation on Junior Payments; No Participation Rights

Except as described below under "-Limitation on Dividends on Parity Stock" and "-Limitation on Certain Payments," the certificate of designations does not prohibit or restrict us or our board of directors from declaring or paying any dividend or distribution (whether in cash, securities or other property, or any combination of the foregoing) on any class or series of our stock, and, unless such dividend or distribution is declared on the STRD Stock, the STRD Stock will not be entitled to participate in such dividend or distribution.

For purposes of the descriptions below under the captions "-Limitation on Dividends on Parity Stock" and "-Limitation on Certain Payments," a regular dividend on the STRD Stock will be deemed to have been paid if such regular dividend is declared and consideration in kind and amount that is sufficient, in accordance with the certificate of designations, to pay such regular dividend is set aside for the benefit of the preferred stockholders entitled thereto.

Limitation on Dividends on Parity Stock

If less than all accrued and unpaid regular dividends on the outstanding STRD Stock in respect of a regular dividend period have been declared and paid as of the regular dividend payment date immediately following such regular dividend period, then, until and unless all accrued and unpaid regular dividends on the outstanding STRD Stock in respect of one full regular dividend period have been paid, no dividends may be declared or paid on any class or series of dividend parity stock unless regular dividends are simultaneously declared on the STRD Stock on a pro rata basis, such that (i) the ratio of (x) the dollar amount of regular dividends so declared per share of STRD Stock to (y) the dollar amount of the total accrued and unpaid regular dividends, in respect of the most recent regular dividend period, per share of STRD Stock immediately before the payment of such regular dividend is no less than (ii) the ratio of (x) the dollar amount of dividends so declared or paid per share of such class or series of dividend parity stock to (y) the dollar amount of the total accrued and unpaid dividends per share of such class or series of dividend parity stock immediately before the payment of such dividend (which dollar amount in this clause (y) will, if dividends on such class or series of dividend parity stock are not cumulative, be the full amount of dividends per share thereof in respect of the most recent dividend period thereof).

Limitation on Certain Payments

As long as any STRD Stock is outstanding, then no dividends or distributions (whether in cash, securities or other property, or any combination of the foregoing) will be declared or paid on any of our "junior stock" (as defined below under the caption "-Definitions"), and neither we nor any of our subsidiaries will purchase, redeem or otherwise acquire for value (whether in cash, securities or other property, or any combination of the foregoing) any of our junior stock or dividend parity stock, in each case unless all accrued regular dividends, if any, on the STRD Stock in respect of the most recently completed regular dividend periods have been declared and paid in full. However, the restrictions described in the preceding sentence will not apply to the following:

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For the avoidance of doubt, the provisions described in this "-Limitation on Certain Payments" section will not prohibit or restrict the payment or other acquisition for value of any debt securities that are convertible into, or exchangeable for, any capital stock.

Our STRK Stock and our STRF Stock contain, and any dividend senior stock that we may issue in the future could contain, provisions similar to the one described in this "-Limitation on Certain Payments" section. In the

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case of our STRK Stock and our STRF Stock, we are prohibited, and, in the case of any dividend senior stock that we may issue in the future, we may be prohibited, from paying dividends on the STRD Stock or purchasing, redeeming or acquiring the STRD Stock until and unless we first pay accumulated dividends in full on our STRK Stock, our STRF Stock and such dividend senior stock.

Tax Considerations

A holder or beneficial owner of the STRD Stock may, in some circumstances, be deemed to have received a distribution that is subject to U.S. federal income tax with respect to any increase in the liquidation preference or any discount at issuance. Applicable withholding taxes (including backup withholding) may be withheld from dividends. In addition, if any withholding taxes (including backup withholding) are paid on behalf of a preferred stockholder, then those withholding taxes may be set off against payments of cash in respect of the STRD Stock or sales proceeds received by, or other funds or assets of, that preferred stockholder. We or any other withholding agent may also require alternative arrangements to collect any withholding tax to ensure that we or such withholding agent is not out-of-pocket for any potential withholding tax liability.

Rights Upon Our Liquidation, Dissolution or Winding Up

If we liquidate, dissolve or wind up, whether voluntarily or involuntarily, then, subject to the rights of any of our creditors, each share of STRD Stock will entitle the holder thereof to receive payment for the following amount out of our assets or funds legally available for distribution to our stockholders, before any such assets or funds are distributed to, or set aside for the benefit of, any liquidation junior stock:

Upon payment of such amount in full on the outstanding STRD Stock, holders of the STRD Stock will have no rights to our remaining assets or funds, if any. If such assets or funds are insufficient to fully pay such amount on all outstanding shares of STRD Stock and the corresponding amounts payable in respect of all outstanding shares of liquidation parity stock, if any, then, subject to the rights of any of our creditors or holders of any outstanding liquidation senior stock, such assets or funds will be distributed ratably on the outstanding shares of STRD Stock and liquidation parity stock in proportion to the full respective distributions to which such shares would otherwise be entitled.

For purposes of the provisions described above in this "-Rights Upon Our Liquidation, Dissolution or Winding Up" section, our consolidation or combination with, or merger with or into, or the sale, lease or other transfer of all or substantially all of our assets (other than a sale, lease or other transfer in connection with our liquidation, dissolution or winding up) to, another person will not, in itself, constitute our liquidation, dissolution or winding up, even if, in connection therewith, the STRD 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.

The certificate of designations for our STRD Stock does not contain any provision requiring funds to be set aside to protect the liquidation preference of the STRD Stock, even though it is substantially in excess of the par value thereof. As such, we may have no assets or funds available for payment on the STRD Stock upon our liquidation, dissolution or winding up. See "Risk Factors-Risks Related to the STRD Stock and This Offering-Although the STRD Stock is senior to our class A common stock and class B common stock, it is junior to our STRF Stock, our STRC Stock, our STRK Stock, our existing and future indebtedness, structurally junior to the liabilities of our subsidiaries and subject to the rights and preferences of any other series of preferred stock then outstanding."

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Voting Rights

The STRD Stock has no voting rights except as described below or as provided in our certificate of incorporation or required by the Delaware General Corporation Law.

Voting and Consent Rights with Respect to Specified Matters

Subject to the other provisions described below, while any STRD Stock is outstanding, each of the following events will require, and cannot be effected without, the affirmative vote or consent of preferred stockholders, and holders of each class or series of voting parity stock, if any, with similar voting or consent rights with respect to such event, representing at least a majority of the combined outstanding voting power of the STRD Stock and such voting parity stock, if any:

(1)any amendment, modification or repeal of any provision of our certificate of incorporation or the certificate of designations that materially adversely affects the special rights, preferences or voting powers of the STRD Stock (other than an amendment, modification or repeal permitted by the provisions described below under the caption "-Certain Amendments Permitted Without Consent"); and

(2)our consolidation or combination with, or merger with or into, another person, or any binding or statutory share exchange or reclassification involving the STRD Stock, in each case unless:

(a) the STRD Stock either (i) remains outstanding after such consolidation, combination, merger, share exchange or reclassification; or (ii) is converted or reclassified into, or is exchanged for, or represents solely the right to receive, preference securities of the continuing, resulting or surviving person of such consolidation, combination, merger, share exchange or reclassification, or the parent thereof;

(b) the STRD Stock that remains outstanding or such preference securities, as applicable, have rights, preferences and voting powers that, taken as a whole, are not materially less favorable (as determined by our board of directors in good faith) to the holders thereof than the rights, preferences and voting powers, taken as a whole, of the STRD Stock immediately before the consummation of such consolidation, combination, merger, share exchange or reclassification; and

(c) the issuer of the STRD Stock that remains outstanding or such preference securities, as applicable, is a corporation duly organized and existing under the laws of the United States of America, any State thereof or the District of Columbia that, if not us, will succeed to us under the certificate of designations and the STRD Stock.

However, a consolidation, combination, merger, share exchange or reclassification that satisfies the requirements of clauses (a), (b) and (c) of paragraph (2) above will not require any vote or consent pursuant to paragraph (1) above. In addition, each of the following will be deemed not to materially adversely affect the rights, preferences or voting powers of the STRD Stock (or cause any of the rights, preferences or voting powers of any such preference securities to be materially less favorable as described above) and will not require any vote or consent pursuant to any of the preceding clauses (1) or (2):

If any event described in paragraphs (1) or (2) above would materially adversely affect the rights, preferences or voting powers of one or more, but not all, classes or series of voting parity stock (which term, solely for these purposes, includes the STRD Stock), then those classes or series whose rights, preferences or voting powers

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would not be materially adversely affected will be deemed not to have voting or consent rights with respect to such event. Furthermore, an amendment, modification or repeal described in paragraph (1) above that materially adversely affects the special rights, preferences or voting powers of the STRD Stock cannot be effected without the affirmative vote or consent of preferred stockholders, voting separately as a class, of at least a majority of the STRD Stock then outstanding.

Certain Amendments Permitted Without Consent

Notwithstanding anything to the contrary described in paragraph (1) above under the caption "-Voting and Consent Rights with Respect to Specified Matters," we may amend, modify or repeal any of the terms of the STRD Stock without the vote or consent of any preferred stockholder to:

Procedures for Voting and Consents

If any vote or consent of the preferred stockholders will be held or solicited, including at a regular annual meeting or a special meeting of stockholders, then our board of directors will adopt customary rules and procedures at its discretion to govern such vote or consent, subject to the other provisions described in this section. Such rules and procedures may include fixing a record date to determine the preferred stockholders (and, if applicable, holders of voting parity stock) that are entitled to vote or provide consent, as applicable, rules governing the solicitation and use of proxies or written consents.

Each share of STRD Stock will be entitled to one vote on each matter on which the holders of the STRD Stock are entitled to vote separately as a class and not together with the holders of any other class or series of stock. The respective voting powers of the STRD Stock and all classes or series of voting parity stock entitled to vote on any matter together as a single class will be determined (including for purposes of determining whether a plurality, majority or other applicable portion of votes has been obtained) in proportion to their respective liquidation amounts. Solely for these purposes, the liquidation amount of the STRD Stock or any such class or series of voting parity stock will be the maximum amount payable in respect of the STRD Stock or such class or series, as applicable, assuming we are liquidated on the record date for the applicable vote or consent (or, if there is no record date, on the date of such vote or consent).

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A consent or affirmative vote of the preferred stockholders pursuant to the provisions described above under the caption "-Voting and Consent Rights with Respect to Specified Matters" may be given or obtained either in writing without a meeting or in person or by proxy at a regular annual meeting or a special meeting of stockholders.

Redemption at Our Option

The STRD Stock is not redeemable at our option except pursuant to an optional redemption or a tax redemption, as described below.

Optional Redemption

Subject to the terms of the certificate of designations, we have the right, at our election, to redeem all, but not less than all, of the outstanding STRD Stock, at any time for cash if the total number of shares of STRD Stock then outstanding is less than 25% of the total number of shares of STRD Stock that have been issued in all offerings we have made of STRD Stock as of such date, taken together. We refer to a redemption pursuant to the provision described above as an "optional redemption."

Tax Redemption

Subject to the terms of the certificate of designations, we have the right, at our election, to redeem all, and not less than all, of the STRD Stock, at any time, for cash if a "tax event" (as defined below under the caption "-Definitions") occurs. We refer to a redemption pursuant to this provision described in this paragraph as a "tax redemption."

Redemption Date

The redemption date will be a business day of our choosing that is no more than 60, nor less than 15, calendar days after the date we send the related redemption notice, as described below.

Redemption Price

The redemption price for a share of STRD Stock called for either optional redemption or tax redemption will be an amount equal to (i) the liquidation preference of such share as of the business day before the date we send the related redemption notice, as described below, plus (ii) declared and unpaid regular dividends, if any, on such share that will have accrued to, but excluding, the redemption date. For the avoidance of doubt, the redemption price will not include payment of any undeclared regular dividends. However, if the redemption date is after a regular record date for a declared regular dividend on the STRD Stock and on or before the next regular dividend payment date, then (a) the holder of such share 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 regular dividend payment date, such declared regular dividend on such share; and (b) the amount referred to in clause (ii) of the preceding sentence will instead be deemed to be zero.

Redemption Notice

We will send to the preferred stockholders notice of the redemption containing certain information set forth in the certificate of designations, including the redemption price and the redemption date.

Fundamental Change Permits Preferred Stockholders to Require Us to Repurchase STRD Stock

Generally

If a fundamental change occurs, then, each preferred stockholder will have the right (the "fundamental change repurchase right") to require us to repurchase some or all of its shares of STRD Stock for cash on a date (the

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"fundamental change repurchase date") 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. We refer to a repurchase of any STRD Stock pursuant to the provisions described in this section as a "repurchase upon fundamental change." Notwithstanding anything to the contrary, in no event will any preferred stockholder be entitled to require us to repurchase a number of shares of STRD Stock that is not a whole number.

The repurchase price (the "fundamental change repurchase price") for a share of STRD Stock tendered for repurchase will be an amount equal to (i) the stated amount of such share, plus (ii) declared and unpaid regular dividends, if any, on such share that will have accrued to, but excluding, the fundamental change repurchase date. For the avoidance of doubt, the fundamental change repurchase price will not include payment of any undeclared regular dividends. However, if the fundamental change repurchase date is after a regular record date for a declared regular dividend on the STRD Stock and on or before the next regular dividend payment date, then (a) the holder of such share 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 regular dividend payment date, such declared regular dividend on such share; and (b) the amount referred to in clause (ii) of the preceding sentence will instead be deemed to be zero.

Notice of Fundamental Change

On or before the 20th calendar day after the effective date of a fundamental change, we will send to each preferred stockholder notice of such fundamental change containing certain information set forth in the certificate of designations, including the fundamental change repurchase date, the fundamental change repurchase price and the procedures preferred stockholders must follow to tender their STRD Stock for repurchase.

Procedures to Exercise the Fundamental Change Repurchase Right

To exercise its fundamental change repurchase right with respect to any STRD Stock, the holder thereof must deliver a notice (a "fundamental change repurchase notice") 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 certificate of designations, including the certificate number of any physical certificate representing any STRD Stock to be repurchased, or must otherwise comply with the depositary procedures in the case of a global certificate.

A holder of STRD Stock that has delivered a fundamental change repurchase notice with respect to any STRD Stock 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 certificate of designations, including the certificate number of any physical certificate representing any STRD Stock with respect to which the withdrawal notice is being delivered, or must otherwise comply with the depositary procedures in the case of a global certificate.

STRD Stock to be repurchased must be delivered to the paying agent (in the case of STRD Stock represented by any physical certificate) or the depositary procedures must be complied with (in the case of STRD Stock represented by any global certificate) for the holder of such STRD Stock 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

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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 STRD Stock pursuant to the provisions described above conflict with any law or regulation that is applicable to us, our compliance with such law or regulation will not be considered to be a breach of those obligations.

Funds Legally Available for Payment of the Fundamental Change Repurchase Price; Covenant Not to Take Certain Actions

Notwithstanding anything to the contrary, (i) we will not be obligated to pay the fundamental change repurchase price of any shares of STRD Stock to the extent, and only to the extent, we do not have sufficient funds legally available to pay the same; and (ii) if we do not have sufficient funds legally available to pay the fundamental change repurchase price of all shares of STRD Stock that are otherwise to be repurchased pursuant to a repurchase upon fundamental change, then (a) we will pay the maximum amount of such fundamental change repurchase price that can be paid out of funds legally available for payment, which payment will be made pro rata to each preferred stockholder based on the total number of shares of STRD Stock of such preferred stockholder that were otherwise to be repurchased pursuant to such repurchase upon fundamental change; and (b) we will cause all such shares as to which the fundamental change repurchase price was not paid to be returned to the holder(s) thereof, and such shares will be deemed to remain outstanding. We will not voluntarily take any action, or voluntarily engage in any transaction, that would result in a fundamental change unless we have sufficient funds legally available to fully pay the maximum aggregate fundamental change repurchase price that would be payable in respect of such fundamental change on all shares of STRD Stock then outstanding.

Repurchase by Third Party

Notwithstanding anything to the contrary, we will be deemed to satisfy our obligations to repurchase STRD Stock pursuant to a repurchase upon fundamental change if (i) one or more third parties conduct the repurchase offer and repurchase tendered STRD Stock 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 STRD Stock 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 STRD Stock.

No Preemptive Rights

Without limiting the rights of preferred stockholders described above, the STRD Stock does not have any preemptive rights to subscribe for or purchase any of our securities.

Calculations

Responsibility; Schedule of Calculations

Except as otherwise provided in the certificate of designations, we will be responsible for making all calculations called for under the certificate of designations or the STRD Stock, including determinations of the last reported sale prices, liquidation preference, fundamental change repurchase price, redemption price and accrued regular dividends on the STRD Stock. We will make all calculations in good faith, and, absent manifest error, our calculations will be final and binding on all preferred stockholders. We will provide a schedule of these calculations to any preferred stockholder or any beneficial owner of any STRD Stock upon written request.

Calculations Aggregated for Each Preferred Stockholder

The composition of the consideration due upon the payment of the fundamental change repurchase price or redemption price for, and the payment on a regular dividend payment date of regular dividends on, the STRD Stock of any preferred stockholder will (in the case of a global certificate, to the extent permitted by, and

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practicable under, the depositary procedures) be computed based on the total number of shares of STRD Stock of such preferred stockholder to be repurchased (in the case of payment of the fundamental change repurchase price) or redeemed (in the case of payment of the redemption price) or held by such preferred stockholder as of the close of business on the related regular record date (in the case of payment of such regular dividends), as applicable. Any cash amounts due to such preferred stockholder in respect thereof will, after giving effect to the preceding sentence, be rounded to the nearest cent.

Notices

We will send all notices or communications to preferred stockholders pursuant to the certificate of designations in writing by first class mail, certified or registered, return receipt requested, or by overnight air courier guaranteeing next day delivery, to the preferred stockholders' respective addresses shown on the register for the STRD Stock. However, in the case of STRD Stock represented by one or more global certificates, we are permitted to send notices or communications to preferred stockholders 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 preferred stockholders in writing.

Definitions

"Affiliate" has the meaning set forth in Rule 144 under the Securities Act as in effect on June 10, 2025.

"Board of directors" means our board of directors or a committee of such board duly authorized to act on behalf of such board.

"Business day" 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.

"Capital stock" 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 such equity.

"Class A common stock" means our class A common stock, $0.001 par value per share.

"Class B common stock" means our class B common stock, $0.001 par value per share.

"Close of business" means 5:00 p.m., New York City time.

"Depositary" means The Depository Trust Company or its successor, or any successor depositary for the applicable shares of STRD Stock.

"Depositary procedures" means, with respect to any transfer, exchange or other transaction involving a global certificate representing any STRD Stock, or any beneficial interest in such certificate, the rules and procedures of the depositary applicable to such transfer, exchange or transaction.

"Dividend junior stock" means any class or series of our stock whose terms do not expressly provide that such class or series will rank senior to, or equally with, the STRD Stock with respect to the payment of dividends (without regard to whether or not dividends accumulate cumulatively). Dividend junior stock includes our class A common stock and our class B common stock. For the avoidance of doubt, dividend junior stock will not include any securities of our subsidiaries.

"Dividend parity stock" means any class or series of our stock (other than the STRD Stock) whose terms expressly provide that such class or series series will rank equally with the STRD Stock with respect to the payment of dividends (without regard to whether or not dividends accumulate cumulatively). For the avoidance of doubt, dividend parity stock will not include any securities of our subsidiaries.

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"Dividend senior stock" means any class or series of our stock whose terms expressly provide that such class or series will rank senior to the STRD Stock with respect to the payment of dividends (without regard to whether or not dividends accumulate cumulatively). Dividend senior stock includes our STRF Stock, our STRC Stock and our STRK Stock. For the avoidance of doubt, dividend senior stock will not include any securities of our subsidiaries.

"Exchange Act" means the U.S. Securities Exchange Act of 1934, as amended.

"Fundamental change" means any of the following events:

(i) either (a) a "person" or "group" (within the meaning of Section 13(d)(3) of the Exchange Act) (other than (w) us; (x) our "wholly owned subsidiaries" (as defined below); (y) any employee benefit plans of ours or our wholly owned subsidiaries; or (z) any "permitted party" (as defined below)), files any report with the SEC indicating that such person or group has become the direct or indirect "beneficial owner" (as defined below) of shares of our common equity representing more than 50% of the voting power of all of our common equity; or (b) a "person" or "group" (within the meaning of Section 13(d)(3) of the Exchange Act) (other than (w) us; (x) our "wholly owned subsidiaries" (as defined below); or (y) any employee benefit plans of ours or our wholly owned subsidiaries), files any report with the SEC indicating that such person or group has become the direct or indirect "beneficial owner" (as defined below) of shares of our class A common stock representing more than 50% of the voting power of all of our class A common stock, provided that, solely for purposes of this clause (b), none of the following will constitute beneficial ownership of our class A common stock: (x) beneficial ownership of our class B common stock; and (y) beneficial ownership by any permitted party of any of our class A common stock issued upon conversion of our class B common stock; or

(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 class A common stock is exchanged for, converted into, acquired for, or constitutes solely the right to receive, other securities, cash or other property; provided, however, that any merger, consolidation, share exchange or combination of us pursuant to which the persons that directly or indirectly "beneficially owned" (as defined below) all classes of our common equity immediately before such transaction directly or indirectly "beneficially own," 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-à-vis each other as immediately before such transaction will be deemed not to be a fundamental change pursuant to this clause (ii).

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 "beneficial owner," whether shares are "beneficially owned," and percentage beneficial ownership, will be determined in accordance with Rule 13d-3 under the Exchange Act.

"Junior stock" means any dividend junior stock or liquidation junior stock.

"Last reported sale price" per share of STRD 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 STRD Stock on such trading day as reported in composite transactions for the principal U.S. national or regional securities exchange on which the STRD Stock is then listed. If the STRD 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

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per share of STRD Stock on such trading day in the over-the-counter market as reported by OTC Markets Group Inc. or a similar organization. If the STRD Stock is not so quoted on such trading day, then the last reported sale price will be the mid-point of the last bid price and the last ask price per share of STRD Stock on such trading day from a nationally recognized independent investment banking firm we select, which may be any of the Agents (or, if no such last bid price or last ask price is available, the fair value of one share of STRD Stock on such trading day determined by a nationally recognized independent investment banking firm we select, which may be any of the Agents).

"Liquidation junior stock" means any class or series of our stock whose terms do not expressly provide that such class or series will rank senior to, or equally with, the STRD Stock with respect to the distribution of assets upon our liquidation, dissolution or winding up. Liquidation junior stock includes our class A common stock and our class B common stock. For the avoidance of doubt, liquidation junior stock will not include any securities of our subsidiaries.

"Liquidation parity stock" means any class or series of our stock (other than the STRD Stock) whose terms expressly provide that such class or series will rank equally with the STRD Stock with respect to the distribution of assets upon our liquidation, dissolution or winding up. For the avoidance of doubt, liquidation parity stock will not include any securities of our subsidiaries.

"Liquidation preference" initially means $100 per share of STRD Stock; provided, however, that, effective immediately after the close of business on each business day after June 10, 2025 (and, if applicable, during the course of a business day on which any sale transaction to be settled by the issuance of STRD Stock is executed, from the exact time of the first such sale transaction during such business day until the close of business of such business day), the liquidation preference per share of STRD Stock is adjusted to be the greatest of (i) the stated amount per share of STRD Stock; (ii) in the case of any business day with respect to which we have, on such business day or any business day during the ten (10) trading day period preceding such business day, executed any sale transaction to be settled by the issuance of STRD Stock, an amount equal to the last reported sale price per share of STRD Stock on the trading day immediately before such business day; and (iii) the arithmetic average of the last reported sale prices per share of STRD Stock for each trading day of the ten (10) consecutive trading days immediately preceding such business day, provided, however, that, if applicable, the reference in this clause (iii) to ten (10) will be replaced by such lesser number of trading days as have elapsed during the period from, and including, June 10, 2025 to, but excluding, such business day. Notwithstanding anything to the contrary in the preceding sentence, at all times before the first date on which we execute any sale transaction to be settled by the issuance of STRD Stock (other than the STRD Stock initially issued on June 10, 2025), which may include sales in this offering, the liquidation preference per share of STRD Stock will be $100. Whenever in this STRD Stock Annex we refer to the liquidation preference of the STRD Stock as of a particular date without setting forth a particular time on such date, such reference will be deemed to be to the liquidation preference immediately after the close of business on such date. For purposes of this definition, references to our execution of any sale transaction to be settled by the issuance of STRD Stock includes any resale of any shares of STRD Stock that we or any of our subsidiaries have purchased or otherwise acquired.

"Liquidation senior stock" means any class or series of our stock whose terms expressly provide that such class or series will rank senior to the STRD Stock with respect to the distribution of assets upon our liquidation, dissolution or winding up. Liquidation senior stock includes our STRF Stock, our STRC Stock and our STRK Stock. For the avoidance of doubt, liquidation senior stock will not include any securities of our subsidiaries.

"Market disruption event" means, with respect to the STRD Stock, on 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 the STRD 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 the STRD Stock or in any options contracts or futures contracts relating to the STRD Stock.

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"Number of incremental diluted shares" means the increase in the number of diluted shares of the applicable class or series of junior stock (determined in accordance with generally accepted accounting principles in the United States, as the same is in effect on June 10, 2025, and assuming net income is positive) that would result from the grant, vesting or exercise of equity-based compensation to directors, employees, contractors and agents (subject to proportionate adjustment for stock dividends, stock splits or stock combinations with respect to such class or series of junior stock).

"Permitted party" means any "person" or "group" (within the meaning of Section 13(d)(3) of the Exchange Act) that consists of, or includes, Michael J. Saylor, the heirs of Michael J. Saylor, or any Affiliates of Michael J. Saylor or the heirs of Michael J. Saylor.

"Person" 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 "person."

"Preferred stockholder," or "holder" of any STRD Stock, means any person in whose name any share of STRD Stock is registered on the registrar's books.

"Regular dividend payment date" means each March 31, June 30, September 30 and December 31 of each year.

"Regular dividend period" means each period from, and including, a regular dividend payment date to, but excluding, the next regular dividend payment date.

"Regular dividend rate" means 10.00% per annum.

"Regular dividends" has the meaning set forth above under the caption "-Regular Dividends-Generally."

"Regular record date" has the following meaning: (i) March 15, in the case of a regular dividend payment date occurring on March 31; (ii) June 15, in the case of a regular dividend payment date occurring on June 30; (iii) September 15, in the case of a regular dividend payment date occurring on September 30; and (iv) December 15, in the case of a regular dividend payment date occurring on December 31.

"Stated amount" means $100 per share of STRD Stock.

"Subsidiary" 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' 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 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.

A "tax event" will be deemed to occur if we have received an opinion of counsel experienced in such matters to the effect that, as a result of:

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"Trading day" means, with respect to the STRD Stock, any day on which (i) trading in the STRD Stock generally occurs on the principal U.S. national or regional securities exchange on which the STRD Stock is then listed or, if the STRD Stock is not then listed on a U.S. national or regional securities exchange, on the principal other market on which the STRD Stock is then traded; and (ii) there is no market disruption event. If the STRD Stock is not so listed or traded, then "trading day" with respect to the STRD Stock means a business day.

"Voting parity stock" means, with respect to any matter as to which preferred stockholders are entitled to vote pursuant to the provisions described above under the caption "-Voting Rights-Voting and Consent Rights with Respect to Specified Matters," each class or series of outstanding dividend parity stock or liquidation parity stock, if any, upon which similar voting rights are conferred and are exercisable with respect to such matter. For the avoidance of doubt, voting parity stock will not include any securities of our subsidiaries.

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

Book Entry, Settlement and Clearance

Global Certificates

The STRD Stock will be initially issued in the form of one or more certificates (the "global certificates") registered in the name of Cede & Co., as nominee of DTC, and will be deposited with the transfer agent as custodian for DTC.

Only persons who have accounts with DTC ("DTC participants") or persons who hold interests through DTC participants may own beneficial interests in a global certificate. We expect that, under procedures established by DTC:

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Book-Entry Procedures for Global Certificates

All interests in a global certificate 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 the STRD Stock. The operations and procedures of DTC are controlled by DTC and may be changed at any time. None of us, the transfer agent or any of the Agents will be responsible for those operations or procedures.

DTC has advised us that it is:

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's participants include securities brokers and dealers (including the Agents), banks and trust companies, clearing corporations and other organizations. Indirect access to DTC's book-entry system is also available to other "indirect participants," 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 STRD Stock 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 certificate, DTC or that nominee will be considered the sole owner or holder of the STRD Stock represented by that global certificate for all purposes under the certificate of designations. Except as provided below, owners of beneficial interests in a global certificate:

As a result, each investor who owns a beneficial interest in a global certificate 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 preferred stockholder under the certificate of designations.

Payments on any global certificates will be made to DTC's nominee as the registered holder of the global certificate. None of us, the transfer agent or the paying agent will have any responsibility or liability for the payment of amounts to owners of beneficial interests in a global certificate, 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 certificate will be governed by standing instructions and customary industry practice and will be the responsibility of those participants or indirect participants and DTC.

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Transfers between participants in DTC will be effected under DTC's procedures and will be settled in same-day funds.

Physical Certificates

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

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MATERIAL UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS

The following discussion is a summary of material U.S. federal income tax considerations relevant to the purchase, ownership and disposition of the shares of STRD Stock issued under this STRD Stock Annex (such shares issued hereunder referred to as "Offered Shares" for purposes of this discussion), but does not purport to be a complete analysis of all potential U.S. federal income tax considerations. This discussion deals only with Offered Shares held as capital assets, within the meaning of Section 1221 of the Code, by holders who purchase such shares in this offering.

This discussion does not cover all aspects of U.S. federal income taxation that may be relevant to the purchase, ownership or disposition of the Offered Shares by prospective investors in light of their particular circumstances. In particular, this discussion does not address all of the tax considerations that may be relevant to persons in special tax situations, including, without limitation, tax-exempt organizations, insurance companies, banks or other financial institutions, dealers in securities or currencies, entities or arrangements treated as partnerships for U.S. federal income tax purposes or other flow-through entities (and investors therein), subchapter S corporations, retirement plans, individual retirement accounts or other tax-deferred accounts, real estate investment trusts, regulated investment companies, persons liable for any alternative minimum tax, "controlled foreign corporations," "passive foreign investment companies," persons subject to special tax accounting rules as a result of any item of gross income with respect to the Offered Shares being taken into account in an applicable financial statement, certain former citizens or former long-term residents of the United States, traders in securities that elect to use a mark-to-market method of tax accounting for their securities holdings, persons that will hold the Offered Shares as a position in a hedging transaction, "straddle," constructive sale, "conversion transaction" or other risk-reduction transaction, persons that acquire any Offered Shares through the directed share program, U.S. holders (as defined herein) whose functional currency is not the U.S. dollar, "qualified foreign pension funds" as described in Section 897(l)(2) of the Code and entities all of the interests of which are held by qualified foreign pension funds, or who are otherwise subject to special treatment under the Code.

Furthermore, this summary is based upon the provisions of the Code, the Treasury Regulations promulgated thereunder and administrative and judicial interpretations thereof, all as of the date hereof. Such authorities may be repealed, revoked, modified or subject to differing interpretations, possibly on a retroactive basis, so as to result in U.S. federal income tax consequences different from those discussed below. This discussion does not address any other U.S. federal tax considerations (such as estate and gift taxes) or any state, local or non-U.S. tax considerations, or the Medicare contribution tax applicable to net investment income of certain non-corporate U.S. holders.

For purposes of this discussion, a "U.S. holder" means a beneficial owner of the Offered Shares that for U.S. federal income tax purposes is

For the purposes of this discussion, a "non-U.S. holder" means a beneficial owner of the Offered Shares that is neither a U.S. holder nor a partnership (including any entity or arrangement that is treated as a partnership for U.S. federal income tax purposes).

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If an entity or arrangement classified as a partnership for U.S. federal income tax purposes holds the Offered Shares, the tax treatment of a partner in such partnership generally will depend upon the status of the partner and the activities of the partnership. A partnership holding the Offered Shares, and partners therein, are urged to consult their tax advisors regarding the tax considerations of acquiring, holding and disposing of the Offered Shares.

We have not sought and will not seek any rulings from the Internal Revenue Service (the "IRS") with respect to the matters discussed below. There can be no assurance that the IRS will not take a different position concerning the tax consequences of the purchase, ownership, and disposition of the Offered Shares or that any such position will not be sustained.

This discussion of material U.S. federal income tax considerations is not intended, and should not be construed, to be tax or legal advice to any particular investor in or holder of the Offered Shares. Prospective investors are advised to consult their tax advisors concerning the application of the U.S. federal income tax laws to their particular situations as well as any tax considerations arising under the laws of any state, local or non-U.S. taxing jurisdiction or any applicable tax treaties, and the possible effect of changes in applicable tax law.

U.S. Holders

Distributions

Distributions made to U.S. holders with respect to the Offered Shares will be taxable as dividend income when paid to the extent of our current or accumulated earnings and profits as determined for U.S. federal income tax purposes. To the extent that the amount of a distribution with respect to the Offered Shares exceeds our current and accumulated earnings and profits, the distribution will be treated first as a tax-free return of capital to the extent of the holder's adjusted tax basis in the Offered Shares, and thereafter as capital gain which will be long-term capital gain if the holder's holding period for the stock exceeds one year at the time of the distribution. Distributions on the Offered Shares constituting dividend income paid to a U.S. holder that is an individual generally will be subject to taxation at preferential rates as qualified dividend income, provided applicable holding period requirements are met and certain other conditions are satisfied. Distributions on the Offered Shares constituting dividend income paid to a U.S. holder that is a corporation generally will qualify for the dividends-received deduction, subject to various limitations and the satisfaction of the applicable holding period requirements.

Dividends that exceed certain thresholds in relation to a corporate U.S. holder's tax basis in the Offered Shares could be characterized as "extraordinary dividends" under the Code. If a corporate U.S. holder that has held the Offered Shares for two years or less before the dividend announcement date receives an extraordinary dividend, the holder generally will be required to reduce its tax basis (but not below zero) in the Offered Shares with respect to which the dividend was made by the non-taxed portion of the dividend. If the amount of the reduction exceeds the U.S. holder's tax basis in the Offered Shares, the excess is treated as gain from the sale or exchange of the Offered Shares. Non-corporate U.S. holders that receive an extraordinary dividend could, under certain circumstances, be required to treat any losses on the sale of the Offered Shares as long-term capital losses to the extent of the extraordinary dividends such U.S. holder receives that qualify for taxation at the preferential rates discussed above.

Deemed Distributions on the Offered Shares

The liquidation preference of the Offered Shares is subject to adjustment in the manner described in this STRD Stock Annex, which adjustment may result in an increase in the liquidation preference. Under Section 305 of the Code, U.S. holders may be treated as receiving a deemed dividend on the Offered Shares upon such an increase in the liquidation preference, although the matter is not clear. Furthermore, if the Offered Shares are issued at a

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discount to their liquidation preference, they may be subject to rules that require the accrual of such discount currently over the deemed term of the Offered Shares as deemed distributions under U.S. tax rules similar to those governing original issue discount for debt instruments. Although the matter is not entirely clear, we believe any such adjustment of liquidation preference in the manner described in this STRD Stock Annex or such a discount should not be treated as giving rise to a deemed distribution on the Offered Shares, but in light of this uncertainty, the IRS or an applicable withholding agent could take a contrary position.

In each case of the foregoing, if the IRS or an applicable withholding agent takes a contrary position, a U.S. holder may be required to include a deemed dividend in income currently with respect to the Offered Shares even though the holder has not received a cash payment. Further, because deemed distributions received by a U.S. holder would not give rise to any cash from which any applicable withholding could be satisfied, if we (or an applicable withholding agent) pay backup withholding on behalf of a U.S. holder (because the U.S. holder failed to establish an exemption from backup withholding), we may, at our option, set off any such payment against, or an applicable withholding agent may withhold such taxes from, payments of cash to the U.S. holder or sales proceeds received by, or other funds or assets of, the U.S. holder, or require alternative arrangements with respect to such withholding taxes.

Sale or Redemption of Offered Shares

A U.S. holder generally will recognize capital gain or loss on a sale, exchange, redemption (including a repurchase) (other than a redemption that is treated as a distribution, as discussed below) or other disposition of the Offered Shares equal to the difference between the amount realized upon the disposition and the holder's adjusted tax basis in the stock so disposed. The capital gain or loss generally will be long-term capital gain or loss if the holder's holding period for the stock exceeds one year at the time of disposition. Long-term capital gains of non-corporate taxpayers generally are taxed at a lower maximum marginal tax rate than the maximum marginal tax rate applicable to ordinary income. The deductibility of capital losses is subject to limitations.

A redemption (including a repurchase) of the Offered Shares will be treated as a sale or exchange described in the preceding paragraph if the redemption, based on the facts and circumstances, is treated for U.S. federal income tax purposes as (i) a "complete termination" of a U.S. holder's equity interest in us, (ii) a "substantially disproportionate" redemption of our stock with respect to such holder, or (iii) being "not essentially equivalent to a dividend" with respect to such holder, each within the meaning of Section 302 of the Code. In determining whether any of these tests has been met, a U.S. holder must take into account not only the Offered Shares and other equity interests in us actually owned by the holder but also other equity interests in us that the holder constructively owns under U.S. federal income tax rules, as well as any rights the holder may have to vote for the election of board members. A U.S. holder that owns (actually or constructively) only an insubstantial percentage of our total equity interests and that exercises no control or management over our affairs may be entitled to sale or exchange treatment on a redemption of the Offered Shares if such holder experiences any reduction in its equity interest (taking into account any constructively owned equity interests) as a result of the redemption.

If a U.S. holder meets none of the alternative tests described above, the redemption will be treated as a distribution subject to the rules described under "U.S. Holders-Distributions." If a redemption of the Offered Shares is treated as a distribution that is taxable as a dividend, the redeeming U.S. holder is urged to consult its tax advisor regarding the allocation of tax basis in the redeemed and remaining shares of STRD Stock.

Because the determination as to whether any of the alternative tests described above is satisfied with respect to any particular U.S. holder will depend upon the facts and circumstances as of the time the determination is made, U.S. holders are urged to consult their tax advisors regarding the tax treatment of a redemption.

Non-U.S. Holders

Distributions

Generally, subject to the discussions below under "Information Reporting and Backup Withholding" and "FATCA," distributions treated as dividends, as described above under "U.S. Holders-Distributions," paid to a

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non-U.S. holder with respect to the Offered Shares that are not effectively connected with the holder's conduct of a trade or business within the United States will be subject to a 30% U.S. withholding tax, or such lower rate as may be specified by an applicable income tax treaty provided the non-U.S. holder furnishes to the withholding agent a properly executed IRS Form W-8BEN or Form W-8BEN-E (or suitable substitute form) certifying that such holder is eligible for treaty benefits. Withholding may also be required in respect of dividends paid to a non-U.S. holder if certain reporting information is not provided, as described below under "-FATCA." If you are subject to withholding at a rate in excess of a reduced rate for which you are eligible under a tax treaty or otherwise, you may be able to obtain a refund of or credit for any amounts withheld in excess of the applicable rate by timely filing a refund claim with the IRS. Non-U.S. holders are encouraged to consult with their tax advisors regarding the possible implications of these withholding requirements on their investment in the Offered Shares.

Subject to the discussions below under "Information Reporting and Backup Withholding" and "FATCA," dividends paid to a non-U.S. holder that are effectively connected with the holder's conduct of a trade or business in the United States and, if an applicable income tax treaty so requires, are attributable to a permanent establishment the holder maintains in the United States, are taxed on a net-income basis at the regular rates and in the manner applicable to U.S. persons. Such non-U.S. holders generally will be required to provide to the applicable withholding agent a properly executed IRS Form W-8ECI (or a suitable substitute form) in order to claim an exemption from, or reduction in, U.S. federal withholding tax. In addition, for such a non-U.S. holder that is a corporation, a "branch profits tax" may be imposed at a 30% rate (or a reduced rate under an applicable income tax treaty) on its effectively connected earnings and profits for the taxable year, as adjusted for certain items.

Sale or Redemption of Offered Shares

Subject to the discussion below under "Information Reporting and Backup Withholding," non-U.S. holders generally will not be subject to U.S. federal income or withholding tax with respect to gain, if any, recognized on a sale, exchange or other taxable disposition of the Offered Shares, other than a redemption that is treated as a distribution as discussed below, unless:

A non-U.S. holder described in the first bullet point above generally will be subject to U.S. federal income tax on the net gain derived from the sale in the same manner as a U.S. holder. A non-U.S. holder that is a foreign corporation will be subject to tax on such gain at regular U.S. federal income tax rates and, in addition, may be subject to a branch profits tax at a 30% rate or a lower rate if so specified by an applicable income tax treaty.

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 the gain recognized, which 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.

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A payment made to a non-U.S. holder in redemption of the Offered Shares may be treated as a dividend, rather than as a payment in exchange for the stock, in the circumstances discussed above under "U.S. Holders-Sale or Redemption of Offered Shares," in which event the payment would be subject to tax as discussed above under "Non-U.S. Holders-Distributions."

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

Deemed Distributions on the Offered Shares

As described above under "U.S. Holders-Deemed Distributions on the Offered Shares," upon an adjustment to the liquidation preference of the Offered Shares, or if the Offered Shares were issued at a discount, the holder may be treated as receiving a deemed distribution. If we (or an applicable withholding agent) pay withholding on behalf of a non-U.S. holder (because such non-U.S. holder failed to establish an exemption from dividend withholding), we may, at our option (or an applicable withholding agent may) set off such payments against, or withhold such taxes from, payments of cash to the non-U.S. holder or sales proceeds received by, or other funds or assets of, the non-U.S. holder, or require alternative arrangements in respect of such withholding taxes.

Multiple Issuances of STRD Stock-Effect of Fungible Trading

We will issue Offered Shares from time to time under this STRD Stock Annex, and may otherwise issue shares of STRD Stock (or resell any shares of STRD Stock that we or any of our subsidiaries have purchased or otherwise acquired) from time to time (such issued or resold shares, the "Additional Shares"). If your Offered Shares trade under the same CUSIP or other identifying number as that of other shares of STRD Stock, those other shares may not be distinguishable from your shares by persons such as subsequent purchasers and withholding agents. If we issue any shares of STRD Stock-whether Offered Shares or Additional Shares-that have a different, and potentially adverse, tax profile or treatment for U.S. federal income tax purposes from your Offered Shares, such profile or treatment could adversely impact your Offered Shares because of the inability to distinguish between your Offered Shares and the shares of STRD Stock subject to such adverse treatment. For example, adverse tax treatment of any shares of STRD Stock could negatively impact the trading price of all shares of STRD Stock in light of fungible trading of all such shares. In addition, the IRS could treat your Offered Shares as subject to the adverse tax consequences applicable to other shares of STRD Stock unless you are able to demonstrate that you acquired your Offered Shares in a specific offering and did not hold such other shares of the STRD Stock that are subject to adverse consequences. Prospective investors are urged to consult their tax advisors regarding these tax considerations.

Please also review the discussion below under "Fast-Pay Stock Regulations" for a discussion about the potential application of those rules to the STRD Stock (including the Offered Shares).

Extraordinary Dividends

If any shares of STRD Stock are treated as being issued at a price that exceeds their liquidation preference, such shares of STRD Stock would constitute "disqualified preferred stock" for purposes of the extraordinary dividend rules. The liquidation preference of the STRD Stock is subject to adjustment in the manner described in this STRD Stock Annex. It is not entirely clear how such an adjustable liquidation preference would be treated for purposes of applying the rules governing disqualified preferred stock and extraordinary dividends. However, it is possible that such adjustment may be taken into account for purposes of the disqualified preferred stock determination. Even if your Offered Shares are not issued at such a price, due to fungible trading of the STRD Stock, your Offered Shares may be considered disqualified preferred stock unless you can clearly demonstrate that you purchased the Offered Shares in an offering other than one in which shares of STRD Stock are issued at such a price. If the Offered Shares held by a corporate U.S. holder were considered disqualified preferred stock (including because such shares are indistinguishable from other shares of STRD Stock that are disqualified

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preferred stock) for any dividend received, the holder generally will be required to reduce its tax basis (but not below zero) in the Offered Shares with respect to which the dividend is received by the non-taxed portion of the dividend. Please also review the discussion above under "U.S. Holders-Distributions" for a discussion of extraordinary dividends.

Sales at a Discount

As discussed above under "U.S. Holders-Deemed Distributions on the Offered Shares," if shares of STRD Stock (including the Offered Shares) are sold at a discount, such shares may be subject to rules that require the accrual of such discount (or a greater discount than the discount that applies to any other shares of STRD Stock) currently over the deemed term of the STRD Stock as deemed distributions under U.S. tax rules similar to those governing original issue discount for debt instruments. Due to fungible trading of the STRD Stock, the IRS or a withholding agent may treat any such discount as resulting in deemed distributions with respect to all shares of STRD Stock, including those not issued at a discount (or issued at a lesser discount). Because any such deemed distributions received by a holder would not give rise to any cash from which any applicable withholding could be satisfied, we may, at our option (or an applicable withholding agent may) set off such payments against, or withhold such taxes from, payments of cash to the holder or sales proceeds received by, or other funds or assets of, the holder, or require alternative arrangements in respect of such withholding taxes.

Fast-Pay Stock Regulations

Under Treasury Regulations promulgated under Section 7701(l) of the Code (the "Fast-Pay Stock Regulations"), if stock of a corporation is structured such that dividends paid with respect to the stock are economically (in whole or in part) a return of the stockholder's investment (rather than a return on the stockholder's investment), then the stock is characterized as "fast-pay stock" and is subject to adverse tax reporting requirements and potentially penalties, as described below. In addition, under the Fast-Pay Stock Regulations, unless clearly demonstrated otherwise, stock is presumed to be fast-pay stock if it is structured to have a dividend that is reasonably expected to decline (as opposed to a dividend rate that is reasonably expected to fluctuate or remain constant) (for such purpose, the dividend rate may be viewed as reasonably expected to decline if we are reasonably expected to stop paying regular dividends on the STRD Stock) or is issued for an amount that exceeds (by more than a de minimis amount, as determined under applicable Treasury Regulations) the amount at which the stockholder can be compelled to dispose of the stock. It is not clear what amount would constitute "de minimis" in the case of stock with a perpetual term.

The determination of whether stock is fast-pay stock is based on all the facts and circumstances. To determine if it is fast-pay stock, stock is examined when issued, and, for stock that is not fast-pay stock when issued, when there is a significant modification in the terms of the stock or the related agreements or a significant change in the relevant facts and circumstances. The relevant tax regulations do not indicate the types of significant changes in facts and circumstances that are intended to give rise to such a determination.

We do not intend to issue any shares of STRD Stock that would be treated as fast-pay stock, and we do not believe that we structured any Offered Shares, or will structure any Additional Shares, such that dividends paid by us with respect to the STRD Stock will be economically a return of a stockholder's investment. Moreover, we have obtained, and we intend to obtain in the future, advice of counsel in connection with offerings of STRD Stock for the purpose of analyzing the consequences of issuing such shares, including in light of any legal developments regarding the definition of fast-pay stock. As the liquidation preference of the STRD Stock is subject to adjustment in the manner described in this STRD Stock Annex, it is generally not expected that the Offered Shares or Additional Shares would be issued at such a level of premium above their liquidation preference at the time of sale of the Offered Shares or Additional Shares so as to implicate the fast-pay stock rules. Nonetheless, there may be increased risk that the IRS could assert that such Offered Shares or Additional Shares constitute fast-pay stock.

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Transactions involving fast-pay stock arrangements are treated as "listed transactions" for U.S. federal income tax purposes. Issuers and holders of any shares of fast-pay stock would be required to report their participation in the transaction on IRS Form 8886 on an annual basis with their U.S. federal income tax returns and would also be required to mail a copy of that form to the IRS Office of Tax Shelter Analysis. Failure to comply with those disclosure requirements could result in the assessment by the IRS of interest, additions to tax and onerous penalties. In addition, an accuracy-related penalty applies under the Code to any reportable transaction understatement attributable to a listed transaction if a significant purpose of the transaction is the avoidance or evasion of U.S. federal income tax. Furthermore, certain material advisors would also be required to file a disclosure statement with the IRS. If we determine that we are required to file an IRS Form 8886 (including a protective filing) in connection with the potential issuance of fast-pay stock with respect to any STRD Stock, we intend to provide public notice to the applicable holders of the STRD Stock, which notice may be by a press release, by publication on our investor relations website, or by filing a current report on Form 8-K with the Securities and Exchange Commission.

Notwithstanding our intent not to issue STRD Stock that would be fast-pay stock, the rules regarding the definition of fast-pay stock are unclear in certain respects and, therefore, the IRS could disagree with our determination and treat Offered Shares or Additional Shares as fast-pay stock. In addition, as discussed above under "-Multiple Issuances of STRD Stock-Effect of Fungible Trading," the treatment of any shares of STRD Stock as fast-pay stock could affect other shares of STRD Stock if all such shares are indistinguishable with each other because they have the same CUSIP or other identifying number. Accordingly, even if your Offered Shares are not fast-pay stock, if the IRS treated any shares of STRD Stock as fast-pay stock, you might be required to demonstrate to the IRS that you purchased your Offered Shares in a different issuance in order to avoid fast-pay stock treatment.

Furthermore, treatment of any shares of STRD Stock as fast-pay stock could adversely affect the trading price of all shares of STRD Stock. Accordingly, holders are strongly urged to consult their tax advisors regarding the Fast-Pay Stock Regulations and their potential consequences to an investment in the Offered Shares.

Information Reporting and Backup Withholding

In general, information reporting will apply with respect to the payment of distributions (including deemed distributions) on the Offered Shares and the payment of proceeds on the sale or other taxable disposition of the Offered Shares, unless a U.S. holder is an exempt recipient such as a corporation. Backup withholding may apply to such payments unless the U.S. holder provides proof of an applicable exemption or a correct taxpayer identification number, and otherwise complies with applicable requirements of the backup withholding rules.

We must report annually to the IRS and to each non-U.S. holder the amount of distributions (including, for this purpose, deemed distributions) paid to such holder and any tax withheld with respect to any dividends, regardless of whether withholding was required. Copies of the information returns reporting distributions and withholding may also be made available to the tax authorities in the country in which the non-U.S. holder resides under the provisions of an applicable income tax treaty. Non-U.S. holders may be subject to backup withholding unless the non-U.S. holder certifies on IRS Form W-8BEN or IRS Form W-8BEN-E (or a suitable substitute form) that it is not a U.S. person (and the withholding agent does not have actual knowledge or reason to know that such holder is a U.S. person) or such holder otherwise establishes an exemption from backup withholding.

Backup withholding is not an additional tax. Any amount withheld under the backup withholding rules from a payment to a U.S. holder or non-U.S. holder is allowable as a credit against the holder's U.S. federal income tax liability and may entitle the holder to a refund, provided that the required information is timely furnished to the IRS.

FATCA

The Foreign Account Tax Compliance Act ("FATCA") and related IRS guidance concerning FATCA impose a 30% U.S. withholding tax on dividends (including, for this purpose, deemed dividends) in respect of Offered

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Shares made to a non-U.S. entity that fails to take required steps to provide information regarding its "United States accounts" or its direct or indirect "substantial United States owners," as applicable, or to make a required certification that it has no such accounts or owners. Although withholding under FATCA would have applied to payments of gross proceeds from the taxable disposition of the Offered Shares, 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. We will not pay any additional amounts to holders of the Offered Shares in respect of any amounts withheld.

Prospective investors should consult their tax advisors about how information reporting and the possible imposition of withholding tax under FATCA may apply to their investment in the Offered Shares.

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PLAN OF DISTRIBUTION

We have entered into the Sales Agreement with the Agents, under which we may offer and sell up to $4,133,799,112.67 of our shares of STRD Stock under this STRD Stock Annex from time to time through the Agents acting as our sales agents, or their respective broker-dealer affiliates (each such entity, a "Selling Agent"). Sales of our STRD Stock, if any, under this STRD Stock may be made by any method that is deemed an "at the market offering" as defined in Rule 415(a)(4) under the Securities Act or any other method permitted by law, which may include negotiated transactions or block trades. We entered into the Sales Agreement on November 4, 2025.

Because there is no minimum offering amount required as a condition to effect this offering of securities under this STRD Stock Annex, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time. We estimate that the total expenses for this offering of STRD Stock, excluding any commissions or expense reimbursement payable to the Agents under the terms of the Sales Agreement, will be approximately $300,000. The remaining sale proceeds, after deducting any other transaction fees, will equal our net proceeds from the sale of such shares.

The offering of our securities pursuant to this STRD Stock Annex and the accompanying base prospectus supplement will terminate upon the earlier of (i) the sale of all securities subject to this STRD Stock Annex, (ii) the termination of this offering in accordance with the terms of the Sales Agreement and (iii) the termination of the Sales Agreement as permitted therein.

This summary of the material provisions of the Sales Agreement does not purport to be a complete statement of its terms and conditions. A copy of the Sales Agreement will be filed with the SEC as an exhibit to a Current Report on Form 8-K filed under the Exchange Act and will be incorporated by reference into the registration statement of which this prospectus supplement forms a part.

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LEGAL MATTERS

The validity of the securities offered hereby will be passed upon by Wilmer Cutler Pickering Hale and Dorr LLP. The Agents are being represented by Davis Polk & Wardwell LLP in connection with the offerings of securities hereunder.

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10.00% Series A Perpetual Stride Preferred Stock

PROSPECTUS SUPPLEMENT

STRD STOCK ANNEX

November 4, 2025