Rock Springs Capital Form 4 Change in insider ownership

SEC Form 4

FORM 4

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

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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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

Rock Springs Capital Management LP

(Last)

(First)

(Middle)

650 SOUTH EXETER ST., SUITE 1070

(Street)

BALTIMORE

21202

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
Theseus Pharmaceuticals, Inc. [ THRX ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
10/12/2021

4. 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 Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	10/12/2021		C⁽¹⁾		349,320	A	⁽²⁾	349,320	I	See Footnote⁽³⁾
Common Stock	10/12/2021		C⁽¹⁾		87,329	A	⁽²⁾	87,329	I	See Footnote⁽⁴⁾
Common Stock	10/12/2021		P⁽⁵⁾		250,000	A	$16	599,320	I	See Footnote⁽³⁾

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
Series B Convertible Preferred Stock	⁽²⁾	10/12/2021		C			349,320	⁽²⁾	⁽²⁾	Common Stock	349,320	⁽²⁾	0	I	See Footnote⁽³⁾
Series B Convertible Preferred Stock	⁽²⁾	10/12/2021		C			87,329	⁽²⁾	⁽²⁾	Common Stock	87,329	⁽²⁾	0	I	See Footnote⁽⁴⁾

1. Name and Address of Reporting Person^*

Rock Springs Capital Management LP

(Last)

(First)

(Middle)

650 SOUTH EXETER ST., SUITE 1070

(Street)

BALTIMORE

21202

(City)

(State)

(Zip)

1. Name and Address of Reporting Person^*

Rock Springs Capital Master Fund LP

(Last)

(First)

(Middle)

C/O WALKERS CORPORATE LIMITED,

CAYMAN CO CENTER 27 HOSPITAL ROAD

(Street)

GEORAGE TOWN

KY-1-9008

(City)

(State)

(Zip)

1. Name and Address of Reporting Person^*

Rock Springs Capital LLC

(Last)

(First)

(Middle)

650 SOUTH EXETER ST., SUITE 1070

(Street)

BALTIMORE

2102

(City)

(State)

(Zip)

Explanation of Responses:

1. The total represents shares received upon conversion of shares of Series B Convertible Preferred Stock.

2. The reported security converted into the issuer's Common Stock on a one-for-one basis automatically immediately prior to the closing of the issuer's initial public offering without payment of further consideration. The shares have no expiration date.

3. The securities reported herein are held of record by Rock Springs Capital Master Fund LP ("Master Fund"). Rock Springs Capital LLC ("RSC") is the general partner of Rock Springs Capital Management LP ("RSCM") which is the investment manager to Master Fund. RSC and RSCM may therefore be deemed to have or share beneficial ownership of the shares held directly by Master Fund.

4. The securities reported herein are held of record by Four Pines Master Fund LP ("Four Pines"). RSC is the general partner of RSCM which is the investment manager to Four Pines. RSC and RSCM may therefore be deemed to have or share beneficial ownership of the shares held directly by Four Pines.

5. Represents shares purchased in the issuer's initial public offering.

Remarks:

	By: /s/ Mark Bussard, Authorized Signatory, Rock Springs Capital Management LP	10/14/2021
	By: /s/ Mark Bussard, Authorized Signatory, Rock Springs Capital Master Fund LP	10/14/2021
	By: /s/ Mark Bussard, Authorized Signatory, Rock Springs Capital LLC	10/14/2021
	** 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 4 (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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Rock Springs Capital Form 4Change in insider ownership