Sierra Oncology : Statement of Changes in Beneficial Ownership (Form 4)

Ownership Submission

FORM 4 Check this box if no longer subject to Section 16, Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549STATEMENT 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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1. Name and Address of Reporting Person * Ashiya Mona 2. Issuer Name and Ticker or Trading Symbol Sierra Oncology, Inc. [SRRA] 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 SIERRA ONCOLOGY, INC. , 1820 GATEWAY DR., SUITE 110 3. Date of Earliest Transaction (Month/Day/Year) (Street) SAN MATEO CA 94404 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Join/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 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code 4. Securities Acquired (A) or Disposed of (D) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) 6. Ownership Form: Direct (D) or Indirect (I) 7. Nature of Indirect Beneficial Ownership Code V Amount (A) or (D) Price

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

1. Title of Derivate Security	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	5. Number of Derivative Securities Acquired (A) or Disposed of (D)	6. Date Exercisable and Expiration Date	7. Title and Amount of Securities Underlying Derivative Security	8. Price of Derivative Security	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s)	10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)	11. Nature of Indirect Beneficial Ownership
Code	V	(A)	(D)	Date Exercisable	Expriation Date	Title	Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
Director	10% Owner	Officer	Other
Ashiya Mona C/O SIERRA ONCOLOGY, INC. 1820 GATEWAY DR., SUITE 110 SAN MATEO, CA94404	X	X

Signatures

/s/ Mona Ashiya; By: Mary Christina Thomson, Attorney-In-Fact	2022-07-01
**Signature of Reporting Person	Date

Explanation of Responses:

(*)	If the form is filed by more than one reporting person, see Instruction 5(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)	These securities are held of record by OrbiMed Private Investments VII, LP ("OPI VII"). OrbiMed Capital GP VII LLC ("GP VII") is the general partner of OPI VII and OrbiMed Advisors LLC ("OrbiMed Advisors") is the managing member of GP VII. The Reporting Person is an employee of OrbiMed Advisors. By virtue of such relationships, GP VII and OrbiMed Advisors may be deemed to have voting power and investment power over the securities held by OPI VII and as a result, may be deemed to have beneficial ownership over such securities. OrbiMed Advisors exercises voting and investment power through a management committee comprised of Carl L. Gordon, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the shares held by OPI VII.
(2)	Each of the Reporting Person, OrbiMed Advisors, GP VII, OrbiMed Genesis GP LLC ("Genesis GP"), and OrbiMed Capital LLC ("OrbiMed Capital") disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of its pecuniary interest therein, if any. This report shall not be deemed an admission that any such entity or person is a beneficial owner of such securities for purpose of Section 16 of the Exchange Act, or for any other purpose.
(3)	These securities are held of record by OrbiMed Genesis Master Fund, L.P. ("Genesis"). Genesis GP is the general partner of Genesis and OrbiMed Advisors is the managing member of Genesis GP. By virtue of such relationships, Genesis GP and OrbiMed Advisors may be deemed to have voting power and investment power over the securities held by Genesis and as a result, may be deemed to have beneficial ownership over such securities. OrbiMed Advisors exercises voting and investment power through a management committee comprised of Carl L. Gordon, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the shares held by Genesis.
(4)	These securities are held of record by OrbiMed Partners Master Fund Limited ("OPM"). OrbiMed Capital is the investment advisor to OPM. OrbiMed Capital is a relying advisor of OrbiMed Advisors. OrbiMed Advisors and OrbiMed Capital exercise voting and investment power through a management committee comprised of Carl L. Gordon, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the shares held by OPM.
(5)	The option fully vested on November 29, 2020.
(6)	Pursuant to the terms of the merger agreement between issuer, GlaxoSmithKline plc ("GSK") and a subsidiary of GSK, this option was cancelled on the effective date of the merger in exchange for a cash payment equal to, on a per share basis, the offer price of $55.00 less the exercise price.
(7)	Pursuant to an agreement with OrbiMed Advisors and GP VII, the Reporting Person is obligated to transfer any securities issued under any such stock options or other awards, or the economic benefit thereof, to OrbiMed Advisors and GP VII, which will in turn ensure that such securities or economic benefits are provided to OPI VII.
(8)	The option fully vested on June 9, 2021.
(9)	The option fully vested on June 8, 2022.
(10)	Pursuant to the terms of the merger agreement between issuer, GSK and a subsidiary of GSK (the "Merger"), the Company's outstanding warrants will be treated in accordance with their respective terms. At the effective time of the Merger, (1) any of the Company's outstanding Series A warrants will be cancelled and represent only the right to receive an amount in cash, without interest, equal to the Black Scholes Value (as defined in the Series A Warrants) which is calculated under the terms of the Series A warrants to be $45.98 per share of our common stock subject to the Series A warrants.

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