Brian James Harris Form 4 Summit Materials / Brian James Harris ownership change

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

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

1. Name and Address of Reporting Person^*

Harris Brian James

(Last) (First) (Middle)

C/O SUMMIT MATERIALS, INC.

1801 CALIFORNIA STREET, SUITE 3500

(Street)

DENVER CO 80202

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Summit Materials, Inc. [ SUM ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
EVP & Chief Financial Officer

3. Date of Earliest Transaction (Month/Day/Year)
02/28/2023

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Class A Common Stock	02/28/2023		M		6,635	A	(1)	202,173(2)(3)	D
Class A Common Stock	02/28/2023		M		5,595	A	(1)	207,768	D
Class A Common Stock	02/28/2023		M		4,785	A	(1)	212,553	D
Class A Common Stock	02/28/2023		A(4)		18,298	A	$0	230,851	D
Class A Common Stock	02/28/2023		F		10,433	D	$29.54	220,418	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	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 (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Restricted Stock Units	(5)	02/28/2023		M			6,636	(6)	(6)	Class A Common Stock	6,636	$0	0	D
Restricted Stock Units	(5)	02/28/2023		M			5,595	(7)	(7)	Class A Common Stock	5,595	$0	5,595	D
Restricted Stock Units	(5)	02/28/2023		M			4,785	(8)	(8)	Class A Common Stock	4,785	$0	9,568	D

Explanation of Responses:

1. 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.

2. Total holdings include shares of Class A Common Stock received pursuant to a stock dividend paid on December 29, 2022.

3. Total holdings include shares of Class A Common Stock acquired through the Issuer's Employee Stock Purchase Plan on April 14, 2022 and October 18, 2022.

4. Reflects shares of Class A Common Stock earned and delivered on performance units previously granted based upon the satisfaction of certain performance criteria.

5. Each restricted stock unit represents a contingent right to receive one share of Class A common stock of the Issuer ("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.

6. These restricted stock units vest in three equal annual installments beginning on February 28, 2021.

7. These restricted stock units vest in three equal annual installments beginning on February 28, 2022.

8. These restricted stock units vest in three equal annual installments beginning on February 28, 2023.

Remarks:

	/s/ Christopher B. Gaskill, as Attorney-in-Fact	03/01/2023
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (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).
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