SEC FORM 3

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^*

GADICKE ANSBERT

(Last)

(First)

(Middle)

C/O MPM CAPITAL

450 KENDALL STREET

(Street)

CAMBRIDGE

02142

(City)

(State)

(Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
02/13/2019

3. Issuer Name and Ticker or Trading Symbol
TCR2 THERAPEUTICS INC. [ TCRR ]

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

X	Director	X	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)
Common Stock	195,902	I	See Footnote⁽¹⁾

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)
1. Title of Derivative Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	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)
Series A Preferred Stock	⁽²⁾	⁽²⁾	Common Stock	79,644	⁽²⁾	I	See Footnote⁽³⁾
Series A Preferred Stock	⁽²⁾	⁽²⁾	Common Stock	52,469	⁽²⁾	I	See Footnote⁽⁴⁾
Series A Preferred Stock	⁽²⁾	⁽²⁾	Common Stock	146,447	⁽²⁾	I	See Footnote⁽⁵⁾
Series A Preferred Stock	⁽²⁾	⁽²⁾	Common Stock	2,195,681	⁽²⁾	I	See Footnote⁽⁶⁾
Series A Preferred Stock	⁽²⁾	⁽²⁾	Common Stock	351,155	⁽²⁾	I	See Footnote⁽⁷⁾
Series A Preferred Stock	⁽²⁾	⁽²⁾	Common Stock	2,421,775	⁽²⁾	I	See Footnote⁽⁸⁾
Series B Preferred Stock	⁽⁹⁾	⁽⁹⁾	Common Stock	9,291	⁽⁹⁾	I	See Footnote⁽³⁾
Series B Preferred Stock	⁽⁹⁾	⁽⁹⁾	Common Stock	5,247	⁽⁹⁾	I	See Footnote⁽⁴⁾
Series B Preferred Stock	⁽⁹⁾	⁽⁹⁾	Common Stock	17,085	⁽⁹⁾	I	See Footnote⁽⁵⁾
Series B Preferred Stock	⁽⁹⁾	⁽⁹⁾	Common Stock	256,163	⁽⁹⁾	I	See Footnote⁽⁶⁾
Series B Preferred Stock	⁽⁹⁾	⁽⁹⁾	Common Stock	35,115	⁽⁹⁾	I	See Footnote⁽⁷⁾
Series B Preferred Stock	⁽⁹⁾	⁽⁹⁾	Common Stock	282,540	⁽⁹⁾	I	See Footnote⁽⁸⁾
Warrants to Purchase Common Stock (Right to Buy)	⁽¹⁰⁾	12/12/2026	Common Stock	42,761	$0.74	I	See Footnote⁽¹⁾
Warrants to Purchase Common Stock (Right to Buy)	⁽¹⁰⁾	12/05/2027	Common Stock	135,508	$0.74	I	See Footnote⁽¹⁾

Explanation of Responses:

1. The reported securities are owned directly by MPM Asset Management LLC. The Reporting Person is a member of MPM Asset Management LLC and disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein.

2. Each share of Series A Preferred Stock is convertible into shares of the Issuer's common stock, par value $0.001 ("Common Stock") on a 6.1938:1 basis. Upon the closing of the Issuer's initial public offering, all shares of Series A Preferred Stock will convert into shares of Common Stock of the Issuer. The Series A Preferred Stock has no expiration date.

3. The reported securities are owned directly by MPM Asset Management Investors BV2014 LLC. The Reporting Person disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein.

4. The reported securities are owned directly by MPM Asset Management Investors SunStates Fund LLC. The Reporting Person is a member of MPM SunStates GP Managing Member LLC and disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein.

5. The reported securities are owned directly by MPM BioVentures 2014 (B), L.P. MPM BioVentures 2014 GP LLC is the general partner of MPM BioVentures 2014 (B), L.P. MPM BioVentures 2014 LLC is the managing member of MPM BioVentures 2014 GP LLC. The Reporting Person is a member of MPM BioVentures 2014 LLC and disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein.

6. The reported securities are owned directly by MPM BioVentures 2014, L.P. MPM BioVentures 2014 GP LLC is the general partner of MPM BioVentures 2014, L.P. MPM BioVentures 2014 LLC is the managing member of MPM BioVentures 2014 GP LLC. The Reporting Person is a member of MPM BioVentures 2014 LLC and disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein.

7. The reported securities are owned directly by MPM SunStates Fund, L.P. MPM SunStates Fund GP LLC is the general partner of MPM SunStates Fund, L.P. MPM SunStates GP Managing Member LLC is the managing member of MPM SunStates Fund GP LLC. The Reporting Person is a member of MPM SunStates Fund GP LLC and disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein.

8. The reported securities are held directly by UBS Oncology Impact Fund, L.P. The general partner of UBS Oncology Impact Fund, L.P. is Oncology Impact Fund (Cayman) Management L.P. The general partner of Oncology Impact Fund (Cayman) Management L.P. is MPM Oncology Impact Management LP. The general partner of MPM Oncology Impact Management LP is MPM Oncology Impact Management GP LLC. The Reporting Person the managing director of MPM Oncology Impact Management GP LLC and disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein.

9. Each share of Series B Preferred Stock is convertible into shares of the Issuer's Common Stock on a 6.1938:1 basis. Upon the closing of the Issuer's initial public offering, all shares of Series B Preferred Stock will convert into shares of Common Stock of the Issuer. The Series B Preferred Stock has no expiration date.

10. The shares subject to this Warrant are fully vested and exercisable.

Remarks:

	/s/ Ansbert Gadicke	02/13/2019
	** 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.
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