TRIL Trillium Therapeutics Inc

FORM 4 [X] 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 * Harrison Rosemary	2. Issuer Name and Ticker or Trading Symbol Trillium Therapeutics Inc. [ TRIL ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director                    _____ 10% Owner __X__ Officer (give title below)    _____ Other (specify below) See Remarks
(Last)          (First)          (Middle) C/O TRILLIUM THERAPEUTICS INC., 2488 DUNWIN DRIVE	3. Date of Earliest Transaction (MM/DD/YYYY) 11/17/2021
(Street) MISSISSAUGA, A6 L5L 1J9 (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)
			Code	V	Amount	(A) or (D)	Price
Common Shares	11/17/2021		D		75	D	(1)	0	D

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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock Option (Right to Buy)	$14.11	11/17/2021		D			180000	(1)	11/12/2030	Common Shares	180000	$0	0	D

Explanation of Responses:

(1)

On November 17, 2021 (the "Closing Date"), PF Argentum Acquisition ULC, an indirect wholly owned subsidiary of Pfizer, Inc. (the "Purchaser") acquired all of the outstanding common shares of Trillium Therapeutics Inc. (the "Issuer") under a plan of arrangement pursuant to the Canada Business Corporations Act (British Columbia) (the "Plan of Arrangement"), whereby Issuer became a wholly owned subsidiary of the Purchaser. At the Effective Time (the "Effective Time") of the Plan of Arrangement, all common shares and equity awards of the Issuer that were issued and outstanding immediately prior to the Effective Time were converted into the right to receive $18.50 per share in cash.

Remarks: Title: Senior Vice President, Corporate Development and Strategy

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Harrison Rosemary C/O TRILLIUM THERAPEUTICS INC. 2488 DUNWIN DRIVE MISSISSAUGA, A6 L5L 1J9			See Remarks

Signatures
/s/ James Parsons, Attorney-in-Fact		11/19/2021
**Signature of Reporting Person		Date