Statement of Changes in Beneficial Ownership (Form 4)

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b). Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * Webster Stephen W 2. Issuer Name and Ticker or Trading Symbol Gritstone bio, Inc. [GRTS] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O GRITSTONE BIO, INC., 5959 HORTON STREET, SUITE 300 3. Date of Earliest Transaction (Month/Day/Year) 04/04/2025 (Street) EMERYVILLE, CA 94608 4. If Amendment, Date Original Filed (Month/Day/Year) 6. Individual or Joint/Group Filing (Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 04/04/2025 J(1) 25,000 D $ 0 0 D

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Stock Option (Right to Buy)

$0.81

04/04/2025

J(1)

103,600

(2)

04/25/2034

Common Stock

103,600

$ 0

0

D

Stock Option (Right to Buy)

$0.76

04/04/2025

J(1)

7,379

(3)

06/16/2034

Common Stock

7,379

$ 0

0

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Webster Stephen W C/O GRITSTONE BIO, INC. 5959 HORTON STREET, SUITE 300 EMERYVILLE, CA 94608	X

Signatures

/s/ Vassiliki Economides, Attorney-in-Fact for Stephen W. Webster		04/08/2025
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Pursuant to the Issuer's Second Modified Plan of Reorganization pursuant to Chapter 11 of the Bankruptcy Code, which was confirmed by the United States Bankruptcy Court for the District of Delaware on April 3, 2025 and became effective on April 4, 2025, each share of the Issuer's common stock and options to purchase the Issuer's common stock outstanding prior to the Issuer's emergence from bankruptcy were cancelled for no value.
(2)	The option vests as to 1/36th of the total grant monthly beginning May 26, 2024 until such time as the option is 100% vested, subject to the continued service of the Reporting Person on each vesting date.
(3)	The option will vest and become exercisable on the earlier of (i) the first anniversary of the date of grant or (ii) the date of the next annual stockholder's meeting to the extent unvested as of such date, subject to continued service through the applicable vesting date.

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