Statement of Changes in Beneficial Ownership (4)

FORM 4 [ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES
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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

1. Name and Address of Reporting Person ^* Mendoza Ruben	2. Issuer Name and Ticker or Trading Symbol Foundation Building Materials, Inc. [ FBM ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) President and CEO
(Last) (First) (Middle) 2520 RED HILL AVE.	3. Date of Earliest Transaction (MM/DD/YYYY) 1/29/2021
(Street) SANTA ANA, CA 92705 (City) (State) (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	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. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. 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)
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	1/29/2021		D⁽¹⁾		69406.00	D	$19.25	0.00	D
Common Stock	1/29/2021		D⁽¹⁾		12500.00	D	$19.25	0.00	I	See Footnote ⁽²⁾
Common Stock	1/29/2021		D⁽¹⁾		21430.00	D	$19.25	0.00	I	See Footnote ⁽³⁾
Common Stock	1/29/2021		D⁽¹⁾		119454.00	D	$19.25	0.00	I	See Footnote ⁽⁴⁾

*Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)*
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. 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		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 of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)			11. Nature of Indirect Beneficial Ownership (Instr. 4)
Restricted Stock Unit	⁽⁵⁾	1/29/2021		D ⁽⁶⁾			163235.00	⁽⁶⁾	⁽⁶⁾	Common Stock	163235.00	⁽⁶⁾	0.00	D
Stock Option	$18.61	1/29/2021		D ⁽⁷⁾			130820.00	⁽⁷⁾	⁽⁷⁾	Common Stock	130820.00	⁽⁷⁾	0.00	D
Stock Option	$15.40	1/29/2021		D ⁽⁷⁾			102319.00	⁽⁷⁾	⁽⁷⁾	Common Stock	102319.00	⁽⁷⁾	0.00	D
Stock Option	$14.00	1/29/2021		D ⁽⁷⁾			60760.00	⁽⁷⁾	⁽⁷⁾	Common Stock	60760.00	⁽⁷⁾	0.00	D
Stock Option	$9.44	1/29/2021		D ⁽⁷⁾			268240.00	⁽⁷⁾	⁽⁷⁾	Common Stock	268240.00	⁽⁷⁾	0.00	D

Explanation of Responses:
(1)	Pursuant to the Agreement and Plan of Merger, dated as of November 14, 2020 (the "Merger Agreement") by and among the Company, ASP Flag Intermediate Holdings, Inc., a Delaware corporation ("Parent") and ASP Flag Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Parent ("Merger Sub"), on January 29, 2021, Merger Sub merged with and into the Company, with the Company continuing as the surviving corporation and a wholly owned subsidiary of Parent (the "Merger"). Pursuant to the Merger Agreement, at the effective time of the Merger, each share of common stock, par value $0.001 per share, of the Company (each, a "Share") was canceled and converted automatically into the right to receive $19.25 per share in cash, without interest and less any applicable tax withholdings.
(2)	Held by the Ruben and Heidi Mendoza Irrevocable Trust dated Jan. 1, 2007. Mr. Mendoza disclaims beneficial ownership of any securities in which he does not have a pecuniary interest.
(3)	Held by Milosophia LLC. Mr. Mendoza disclaims beneficial ownership of any securities in which he does not have a pecuniary interest.
(4)	Held by The Mendoza Family Trust dated June 3, 2003.
(5)	Each Restricted Stock Unit ("RSU") represents a contingent right to receive one Share.
(6)	Pursuant to the Merger Agreement, each RSU outstanding immediately prior to the consummation of the Merger was canceled and converted into the right to receive, without interest and less any applicable tax withholdings, $19.25 in cash.
(7)	Pursuant to the Merger Agreement, each option to purchase shares of common stock that is outstanding immediately prior to the consummation of the Merger will fully vest and be converted into the right to receive an amount in cash, without interest and less any applicable tax withholdings, equal to the product of (x) the remainder, if positive, of $19.25 minus the exercise price per share of the Company stock option multiplied by (y) the number of shares of common stock. If the exercise price per share of a Company stock option equals or exceeds $19.25, the Company stock option will be canceled.

Reporting Owners
Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
Mendoza Ruben 2520 RED HILL AVE. SANTA ANA, CA 92705	X		President and CEO