Please wait

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* Omega Fund VI, L.P. (Last) (First) (Middle) 888 BOYLSTON STREET, SUITE 1111 (Street) BOSTON MA 02199 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 10/06/2021	3. Issuer Name and Ticker or Trading Symbol Theseus Pharmaceuticals, Inc. [ THRX ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) 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) Form filed by One Reporting Person X 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
Series B Preferred Stock	(1)	(1)	Common Stock	523,979	(1)	D(2)

1. Name and Address of Reporting Person* Omega Fund VI, L.P. (Last) (First) (Middle) 888 BOYLSTON STREET, SUITE 1111 (Street) BOSTON MA 02199 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Omega Fund VI GP, L.P. (Last) (First) (Middle) 888 BOYLSTON STREET, SUITE 1111 (Street) BOSTON MA 02199 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Omega Fund VI GP Manager, Ltd. (Last) (First) (Middle) 888 BOYLSTON STREET, SUITE 1111 (Street) BOSTON MA 02199 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Stampacchia Otello (Last) (First) (Middle) 888 BOYLSTON STREET, SUITE 1111 (Street) BOSTON MA 02199 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Nessi Claudio (Last) (First) (Middle) 888 BOYLSTON STREET, SUITE 1111 (Street) BOSTON MA 02199 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Paster Anne-Mari (Last) (First) (Middle) 888 BOYLSTON STREET, SUITE 1111 (Street) BOSTON MA 02199 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. Omega Fund VI, L.P. ("Omega VI") holds 693,152 shares of the Issuer's Series B Preferred Stock. The Series B Preferred Stock will automatically convert immediately prior to and in connection with the closing of a public offering of the issuer's securities pursuant to an effective registration statement under the Securities Act of 1933, as amended (the "Securities Act"), into 523,979 shares of common stock on a 1-for-1.32286 reverse split basis.

2. The reported securities are beneficially owned by Omega VI. The reported securities may be deemed to be beneficially owned by each of Omega Fund VI GP, L.P. ("Omega VI GP"), as the general partner of Omega VI, and Omega Fund VI GP Manager, Ltd. ("Omega VI GP Manager"), as the general partner of Omega VI GP. Otello Stampacchia, Claudio Nessi and Anne-Mari Paster are all the shareholders and directors of Omega VI GP Manager and have shared voting and investment power over the shares held by Omega VI and, as a result, may each be deemed to beneficially own the reported securities. Each of the Reporting Persons disclaims beneficial ownership of the reported securities, except to the extent of his, her or its pecuniary interest therein.

Remarks:

	/s/ Anne-Mari Paster, **Signature of Anne-Mari Paster as as an authorized signatory of each Reporting Person	10/06/2021
	** 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.