Brian Harris - Jul 30, 2022 Form 4 Insider Report for Summit Materials, Inc. (SUM)

Role: EVP & Chief Financial Officer
Signature: /s/ Christopher B. Gaskill, as Attorney-in-Fact
Stock symbol: SUM
Transactions as of: Jul 30, 2022
Transactions value $: -$160,961
Form type: 4
Date filed: 8/1/2022, 06:25 PM
Previous filing: Mar 3, 2022
Next filing: Mar 1, 2023

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	SUM	Class A Common Stock	Options Exercise		+13.3K	+7.22%		198K	Jul 30, 2022	Direct	F1, F2
transaction	SUM	Class A Common Stock	Tax liability	-$161K	-5.85K	-2.96%	$27.51	192K	Jul 30, 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	-13.3K	-100%	$0.00^*	0	Jul 30, 2022	Class A Common Stock	13.3K		Direct	F3, F4

* 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	Includes 648 shares acquired through the Issuer's Employee Stock Purchase Plan on April 14, 2022.
F3	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.
F4	The Reporting Person was granted 26,656 restricted stock units that vest in two equal installments beginning on July 30, 2021.