Initial Registration Statement for Employee Benefit Plan (Form S-8)

As filed with the Securities and Exchange Commission on August 5, 2026

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933
EXELIXIS, INC. (Exact name of registrant as specified in its charter)

Delaware			04-3257395
(State or other jurisdiction of incorporation or organization)			(I.R.S. Employer Identification Number)

1851 Harbor Bay Parkway

Alameda, CA 94502

(Address of Principal Executive Offices, including Zip Code)

AMENDED AND RESTATED 2017 EQUITY INCENTIVE PLAN (Full Title of the Plan)

Michael M. Morrissey

President and Chief Executive Officer

Exelixis, Inc.

1851 Harbor Bay Parkway

Alameda, CA 94502

(650) 837-7000

(Name, Address, and Telephone Number, including Area Code, of Agent for Service)

Copies to:
Brenda J. Hefti			Raquel Fox
Senior Vice President and General Counsel			Skadden, Arps, Slate, Meagher & Flom LLP
Exelixis, Inc.			1440 New York Ave NW
1851 Harbor Bay Parkway			Washington, DC 20005
Alameda, CA 94502

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

Large accelerated filer

ý

Accelerated filer

¨

Non-accelerated filer

¨

Smaller reporting company

¨

Emerging growth company

¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ¨

EXPLANATORY NOTE

This Registration Statement on Form S-8 is being filed by Exelixis, Inc. (the "Company") for the purpose of registering an additional 2,000,000 shares of common stock, par value $0.001 per share (the "Common Stock") to be issued pursuant to the Amended and Restated 2017 Equity Incentive Plan (the "2017 Plan"). The shares of the Common Stock previously reserved for issuance under the 2017 Plan were registered on the Company's Registration Statements on Form S-8 previously originally filed with the Securities and Exchange Commission (the "Commission") on May 25, 2017 (File No. 333-218236), August 1, 2018 (File No. 333-226493), August 6, 2020 (File No. 333-241667) and August 9, 2022 (File No. 333-266707) (as amended, collectively, the "Prior Registration Statements").

This Registration Statement on Form S-8 relates to securities of the same class as that to which the Prior Registration Statements relate, and is submitted in accordance with General Instruction E to Form S-8 regarding Registration of Additional Securities. Pursuant to General Instruction E of Form S-8, the contents of the Prior Registration Statements, to the extent relating to the registration of Common Stock issuable under the 2017 Plan, are incorporated herein by reference and made part of this Registration Statement, except as amended hereby.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE

The following documents filed by the Company with the Commission are incorporated by reference into this Registration Statement:

•The Company's Annual Report on Form 10-K for the fiscal year ended January 2, 2026 (the "Form 10-K"), filed on February 10, 2026;

•The Company's Quarterly Report on Form 10-Q for the fiscal quarter ended April 3, 2026, filed on May 5, 2026;

•The Company's Quarterly Report on Form 10-Q for the fiscal quarter ended July 3, 2026, filed on August 5, 2026;

•The Company's Current Reports on Form 8-K filed on May 5, 2026 (but not including any Item 2.02 and Exhibit 99.1 of such filing, which were furnished under applicable Commission rules rather than filed), May 29, 2026, and August 5, 2026; and

•The description of the Company's common stock that is contained in the Company's Registration Statement on Form 8-A (File No. 000-30235), filed with the Commission on April 6, 2000, pursuant to Section 12 under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), including any amendment or report filed for the purpose of updating such description, including Exhibit 4.2 to the Form 10-K.

All reports and other documents subsequently filed by the Company pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act after the date of this Registration Statement and prior to the filing of a post-effective amendment that indicates that all securities offered have been sold or that deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be a part of this Registration Statement from the date of the filing of such reports and documents. Notwithstanding the foregoing, unless specifically stated to the contrary, none of the information that the Company discloses under Items 2.02 or 7.01 of any Current Report on Form 8-K that it may from time to time furnish to the Commission will be incorporated by reference into, or otherwise included in, this Registration Statement. Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein, or in any other subsequently filed document that also is or is deemed to be incorporated by reference herein, modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

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ITEM 8. EXHIBITS

Exhibit Number

Exhibit Description

Incorporation by Reference

Filed Herewith

Form

File Number

Exhibit/ Appendix Reference

Filing Date

4.1

Restated Certificate of Incorporation of Exelixis, Inc.

10-Q

000-30235

3.1

8/5/2021

4.2

Certificate of Change of Registered Agent and/or Registered Office of Exelixis, Inc.

10-Q

000-30235

3.2

4/30/2024

4.3

Amended and Restated Bylaws of Exelixis, Inc.

8-K

000-30235

3.1

12/20/2023

5.1

Opinion of Skadden, Arps, Slate, Meagher & Flom LLP

X

23.1

Consent of independent registered public accounting firm

X

23.2

Consent of Skadden, Arps, Slate, Meagher & Flom LLP (included in Exhibit 5.1)

X

24.1

Power of Attorney (contained on signature page hereto)

X

99.1

Exelixis, Inc. 2017 Equity Incentive Plan

8-K

000-30235

10.1

5/29/2026

107

Filing Fee Table

X

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Alameda, State of California, on August 5, 2026.

EXELIXIS, INC.
By:			/s/ Michael M. Morrissey
			Michael M. Morrissey, Ph. D.
			President and Chief Executive Officer

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Michael M. Morrissey, Christopher J. Senner and Brenda J. Hefti and each or any one of them, his or her true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them, or their or his or her substitutes or substitute, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

Signature

Title

Date

/s/ MICHAEL M. MORRISSEY

Director, President and

August 5, 2026

Michael M. Morrissey, Ph.D.

Chief Executive Officer (Principal Executive Officer)

/s/ CHRISTOPHER J. SENNER

Executive Vice President and

August 5, 2026

Christopher J. Senner

Chief Financial Officer (Principal Financial and Accounting Officer)

/s/ STELIOS PAPADOPOULOS

Chairman of the Board

August 5, 2026

Stelios Papadopoulos, Ph.D.

/s/ MARY C. BECKERLE

Director

August 5, 2026

Mary C. Beckerle, Ph.D.

/s/ S. GAIL ECKHARDT

Director

August 5, 2026

S. Gail Eckhardt, M.D.

/s/ MARIA C. FREIRE

Director

August 5, 2026

Maria C. Freire, Ph.D.

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Signature

Title

Date

/s/ TOMAS J. HEYMAN

Director

August 5, 2026

Tomas J. Heyman

/s/ DAVID E. JOHNSON

Director

August 5, 2026

David E. Johnson

/s/ ROBERT L. OLIVER

Director

August 5, 2026

Robert L. Oliver, Jr.

/s/ GEORGE POSTE

Director

August 5, 2026

George Poste, DVM, Ph.D., FRS

/s/ JULIE A. SMITH

Director

August 5, 2026

Julie A. Smith

/s/ JACK L. WYSZOMIERSKI

Director

August 5, 2026

Jack L. Wyszomierski

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