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

As filed with the Securities and Exchange Commission on February 17, 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

IDEAYA Biosciences, Inc.

(Exact name of Registrant as specified in its charter)

2019 Incentive Award Plan

2019 Employee Stock Purchase Plan

(Full Title of the Plan)

Yujiro Hata

President and Chief Executive Officer

IDEAYA Biosciences, Inc.

5000 Shoreline Court, Suite 300

South San Francisco, California 94080

(650) 443-6209

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

Copies to:

Mark V. Roeder, Esq.

John C. Williams, Esq.

Latham & Watkins LLP

140 Scott Drive

Menlo Park, California 94025

Telephone: (650) 328-4600

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 is being filed with the Securities and Exchange Commission (the "Commission") for the purpose of registering an additional 4,389,827 shares of common stock, par value $0.0001 per share ("common stock"), of IDEAYA Biosciences, Inc. (the "Registrant") issuable under the following employee benefit plans for which registration statements of the Registrant on Form S-8 (File Nos. 333-231784, 333-237362, 333-254617, 333-263657, 333-270334, 333-277189, 333-285028) are effective: (i) the IDEAYA Biosciences, Inc. 2019 Incentive Award Plan which, as a result of the operation of an automatic annual increase provision therein, added 3,511,862 shares of common stock and (ii) the IDEAYA Biosciences, Inc. Employee Stock Purchase Plan which, as a result of the operation of an automatic annual increase provision therein, added 877,965 shares of common stock.

PART I

INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

The information called for in Part I of Form S-8 is not being filed with or included in this Form S-8 (by incorporation by reference or otherwise) in accordance with the rules and regulations of the Securities and Exchange Commission (the "SEC").

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

In this registration statement, IDEAYA Biosciences, Inc. is sometimes referred to as "Registrant," "we," "us" or "our."

INCORPORATION BY REFERENCE OF CONTENTS OF REGISTRATION STATEMENTS ON FORM S-8

Pursuant to Instruction E of Form S-8, the contents of the Registration Statements on Form S-8 filed with the SEC on May 28, 2019 (File No. 333-231784), March 24, 2020 (File No. 333-237362), March 23, 2021 (File No. 333-254617), March 17, 2022 (File No. 333-263657), March 7, 2023 (File No. 333-270334), February 20, 2024 (File No. 333-277189), and February 18, 2025 (File No. 333-285028) are incorporated by reference herein; except for Item 8, which is being updated by this Registration Statement.

Item 3. Incorporation of Documents by Reference.

The SEC allows us to incorporate by reference the information we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this registration statement, and later information filed with the SEC will update and supersede this information. We hereby incorporate by reference into this registration statement the following documents previously filed with the SEC:

All documents that the Registrant subsequently files pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act prior to the filing of a post-effective amendment to the registration statement which indicates that all of the shares of common stock offered have been sold or which deregisters all of such shares then remaining unsold, shall be deemed to be incorporated by reference in this registration statement and to be a part hereof from the date of the filing of such documents; except as to any portion of any future annual or quarterly report to stockholders or document or current report furnished under current Items 2.02 or 7.01 of Form 8-K, and exhibits furnished on such form that relate to such items, that is not deemed filed under such provisions. For the purposes of 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 to the extent that a statement contained herein or in any other subsequently filed document which 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.

Under no circumstances will any information filed under current Items 2.02 or 7.01 of Form 8-K, and exhibits furnished on such form that relate to such items, be deemed incorporated herein by reference unless such Form 8-K expressly provides to the contrary.

Item 8. Exhibits.

Exhibit Index

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, 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 South San Francisco, California, on this 17th day of February, 2026.

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Yujiro Hata and Joshua Bleharski, Ph.D., and each of them acting individually, as his true and lawful attorneys-in-fact and agents, each with full power of substitution, for him in any and all capacities, to sign any and all amendments to this Registration Statement, including post-effective amendments or any abbreviated registration statement and any amendments thereto filed pursuant to Rule 462(b) increasing the number of securities for which registration is sought, and to file the same, with all exhibits thereto and other documents in connection therewith, with the SEC, granting unto said attorneys-in-fact and agents, with full power of each to act alone, 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 for all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or his or their substitute or 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 by the following persons in the capacities and on the dates indicated.