Mary Christina Thomson - 04 Feb 2022 Form 4 Insider Report for Sierra Oncology, Inc.

Role: General Counsel, CCO & Sec'y
Signature: /s/ Mary Christina Thomson
Issuer symbol: N/A
Transactions as of: 04 Feb 2022
Net transactions value: -$33,480
Form type: 4
Filing time: 04 Feb 2022, 15:08:39 UTC
Previous filing: 28 Jan 2022
Next filing: 04 Mar 2022
SEC: View on sec.gov

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	SRRA	Common Stock	Options Exercise	$26,080	+2,000		$13.04	2,000	04 Feb 2022	Direct
transaction	SRRA	Common Stock	Sale	$59,560	-2,000	-100%	$29.78	0	04 Feb 2022	Direct	F1

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)	Options Exercise	$0	+2,000		$0.000000^*	0	04 Feb 2022	Common Stock	2,000	$13.04	Direct	F2

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

Explanation of Responses:

Id	Content
F1	The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on January 21, 2022. The Reporting Person is subject to a Lock-Up Letter Agreement that expires on April 26, 2022. The sale of shares is a permissible exemption under the terms of the Lock-Up Letter Agreement.
F2	On July 28, 2021, the option vested as to 25% of the total shares granted on July 28, 2020, with the remaining shares from that grant vesting in equal monthly installments over the following 36 months, with 100% of the total shares vested on July 28, 2024, subject to the Reporting Person's provision of service to the Issuer on each vesting date.