Anne P. Noonan - Feb 28, 2022 Form 4 Insider Report for Summit Materials, Inc. (SUM)

Role: President & CEO, Director
Signature: /s/ Christopher B. Gaskill, as Attorney-in-Fact
Stock symbol: SUM
Transactions as of: Feb 28, 2022
Transactions value $: -$152,510
Form type: 4
Date filed: 3/1/2022, 04:52 PM
Previous filing: Jul 22, 2021
Next filing: Mar 3, 2022

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	SUM	Class A Common Stock	Options Exercise		+16.9K	+20.89%		98.1K	Feb 28, 2022	Direct	F1
transaction	SUM	Class A Common Stock	Tax liability	-$153K	-4.89K	-4.98%	$31.22	93.2K	Feb 28, 2022	Direct

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	SUM	Restricted Stock Units	Options Exercise	$0	-16.9K	-33.33%	$0.00	33.9K	Feb 28, 2022	Class A Common Stock	16.9K		Direct	F2, F3

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

Explanation of Responses:

Id	Content
F1	Reflects restricted stock units that upon vesting converted into shares of Class A common stock of the Issuer ("Class A Common Stock") on a one-for-one basis.
F2	Each restricted stock unit represents a contingent right to receive one share of Class A Common Stock. The restricted stock units will be settled in either Class A Common Stock or cash (or a combination thereof) at the discretion of the Issuer's Human Capital and Compensation Committee.
F3	The Reporting Person was granted 50,838 restricted stock units that vest in three equal annual installments beginning on February 28, 2022.