Form S-8 ImageneBio, Inc.

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

Registration No. 333-   

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

IMAGENEBIO, INC.

(Exact name of registrant as specified in its charter)

12526 High Bluff Drive, Suite 345

San Diego, CA 92130

(858) 345-6265

(Address, including zip code, and telephone number, including area code, of Registrant’s principal executive offices)

ImageneBio, Inc. Amended and Restated 2025 Equity Incentive Plan

(Full title of the plans)

Kristin Yarema, Ph.D.

Chief Executive Officer

12526 High Bluff Drive, Suite 345

San Diego, CA 92130

(858) 345-6265

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Thomas A. Coll, Esq.

Asa M. Henin, Esq.

Brittany K. Wightman, Esq.

Cooley LLP

10265 Science Center Drive

San Diego, CA 92121

(858) 550-6000

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.

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 (this “Registration Statement”) is being filed by ImageneBio, Inc. (the “Registrant”) for the purpose of increasing the number of securities of the same class as other securities for which Registration Statements on Form S-8 relating to the same employee benefit plan are effective. The Registrant previously registered its shares of common stock, par value $0.001 per share (the “Common Stock”), for issuance under the Registrant’s 2025 Equity Incentive Plan (the “2025 Plan”) under the Registrant’s Registration Statements on Form S-8 filed with the Securities and Exchange Commission (the “Commission”) on November  12, 2025 (File No. 333-291449) and March  10, 2026 (File No. 333-294174) (the “Prior Registration Statements”). In accordance with General Instruction E to Form S-8, the contents of the Prior Registration Statements are hereby incorporated by reference.

PART II

Item 3. Incorporation of Certain Documents by Reference.

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

In addition, all documents subsequently filed by the Registrant with the Commission pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act (other than Current Reports furnished under Item 2.02 or Item 7.01 of exhibits furnished on such form that relate to such items and other portions of documents that are furnished but not filed or are otherwise not incorporated into registration statements pursuant to the applicable rules promulgated by the Commission), prior to the filing of a post-effective amendment to this Registration Statement that indicates that all securities offered hereby have been sold or that deregisters all securities remaining unsold, shall be deemed to be incorporated by reference in this Registration Statement and to be a part hereof from the date of filing of such documents.

Any statement, including financial statements, 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 therein 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.

Item 8. Exhibits.

SIGNATURES

Pursuant to the requirements of the Securities Act, 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 San Diego, State of California, on the 5th day of August 2026.

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Kristin Yarema, Ph.D. as the individual’s 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 to this Registration Statement, and to file the same, with all exhibits thereto and other documents in connection therewith, with the Commission, granting unto said attorney-in-fact and agent, full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agent or their substitutes, may lawfully do or cause to be done by virtue hereof.

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