Flaherty Keith T. Form 3 Checkmate Pharmaceuticals / Keith T. Flaherty ownership change

SEC Form 3

FORM 3

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

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

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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1. Name and Address of Reporting Person^*

Flaherty Keith T.

(Last) (First) (Middle)

C/O CHECKMATE PHARMACEUTICALS, INC.

245 MAIN STREET, 2ND FLOOR

(Street)

CAMBRIDGE MA 02142

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
08/06/2020

3. Issuer Name and Ticker or Trading Symbol
Checkmate Pharmaceuticals, Inc. [ CMPI ]

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

X	Director	10% Owner
	Officer (give title below)	Other (specify below)

5. 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 Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock Option (right to buy)	03/27/2020	03/27/2028	Common Stock	4,012	2.47	D
Stock Option (right to buy)	(1)	03/27/2029	Common Stock	22,736	2.62	D

Explanation of Responses:

1. 33.3% of the shares subject to such option vested and became exercisable on March 27, 2020 and the remainder of the shares vest in substantially equal monthly installments for a period of 24 months thereafter, subject to the Reporting Person's continuous service to the Issuer on each such date.

Remarks:

Exhibit 24 - Power of Attorney

	/s/ Kleem Chaudhary, attorney-in-fact	08/06/2020
	** 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 5 (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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