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

OMB APPROVAL OMB Number: 3235-0104 Estimated average burden hours per response: 0.5

1. Name and Address of Reporting Person* SOUTHWELL DAVID P (Last) (First) (Middle) C/O TSCAN THERAPEUTICS, INC. 830 WINTER STREET (Street) WALTHAM MA 02451 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 07/15/2021	3. Issuer Name and Ticker or Trading Symbol TScan Therapeutics, Inc. [ TCRX ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director 10% Owner X Officer (give title below) Other (specify below) Chief Executive 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)
Voting Common Stock	86,899	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
Employee Stock Option (right to buy)	(1)	10/08/2028	Voting Common Stock	121,350	1.97	D
Employee Stock Option (right to buy)	(1)	02/04/2029	Voting Common Stock	69,831	1.97	D
Employee Stock Option (right to buy)	(2)	12/17/2029	Voting Common Stock	200,822	2.46	D
Employee Stock Option (right to buy)	(3)	01/26/2031	Voting Common Stock	518,504	5.82	D

Explanation of Responses:

1. The shares originally subject to this option vested over 4 years of service following October 9, 2018, with 25% vesting upon completion of 1 year of continuous service to the Issuer and the balance vesting in 36 equal monthly installments thereafter. In addition, all of the shares subject to this option shall vest and become fully exercisable upon a Change of Control (as defined in the option agreement).

2. The shares subject to this option vested over 4 years of service following December 5, 2019, with 25% vesting upon completion of 1 year of continuous service to the Issuer and the balance vesting in 36 equal monthly installments thereafter.

3. The shares subject to this option vested over 4 years of service following January 25, 2021, with 25% vesting upon completion of 1 year of continuous service to the Issuer and the balance vesting in 36 equal monthly installments thereafter.

Remarks:

	/s/ David Southwell	07/15/2021
	** 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.