Mark Kowalski - Jan 28, 2022 Form 4 Insider Report for Sierra Oncology, Inc. (SRRA)

Role: Chief, Research & Early Dev
Signature: /s/ Mark M. Kowalski / By: Mary Christina Thomson, Attorney-In-Fact
Stock symbol: SRRA
Transactions as of: Jan 28, 2022
Transactions value $: $0
Form type: 4
Date filed: 1/28/2022, 05:34 PM

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	SRRA	Stock Option (Right to Buy)	Award	$0	+12.3K		$0.00	12.3K	Jan 28, 2022	Common Stock	12.3K	$12.15	Direct	F1

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	On August 12, 2020, the Reporting Person was granted an option to purchase 49,000 shares of common stock. The option vests based on the satisfaction by Issuer of certain performance criteria. The achievement of one of the performance criteria resulted in vesting of the option as to 12,250 shares.