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* Gengos Andrew (Last) (First) (Middle) 128 SPRING ST, BUILDING A, SUITE 510 (Street) LEXINGTON MA 02421 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 06/17/2021	3. Issuer Name and Ticker or Trading Symbol Cyteir Therapeutics, Inc. [ CYT ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner X Officer (give title below) Other (specify below) Chief Business Officer	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)
Common Stock	73,534(1)	D

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)	(2)	03/23/2030	Common Stock	55,151	$1.19	D
Stock Option (Right to Buy)	(3)	03/23/2030	Common Stock	147,070	$1.19	D
Stock Option (Right to Buy)	(4)	02/21/2031	Common Stock	102,927	$7.09	D

Explanation of Responses:

1. Includes 4,595 shares acquired upon early exercise of an option, which are subject to forfeiture until they vest.

2. The option vests as to 75% of the underlying shares of common stock on February 24, 2023, and as to the remaining shares underlying the award in 12 equal monthly installments thereafter, subject to the Reporting Person's continued employment with the Issuer through the applicable vesting date.

3. The option vests as to 25% of the underlying shares of common stock on February 24, 2021, and as to the remaining shares underlying the award in 36 equal monthly installments thereafter, subject to the Reporting Person's continued employment with the Issuer through the applicable vesting date.

4. The option will become exercisable as to 1/36th of the underlying shares of common stock at the end of each successive one-month period following the vesting commencement date, February 5, 2021, until the option is fully vested on the third anniversary of the vesting commencement date, subject to the Reporting Person's continued employment with the Issuer through the applicable vesting date.

Remarks:

	By: /s/ Andrew Gengos	06/17/2021
	** 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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