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* Pontifax Management 4 G.P. (2015) Ltd. (Last) (First) (Middle) 14 SHENKAR STREET, BEIT OFEK (Street) HERZLIYA PITUACH L3 46140 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 04/07/2020	3. Issuer Name and Ticker or Trading Symbol Keros Therapeutics, Inc. [ KROS ]
		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) 04/07/2020
			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
Call Options (obligation to sell)(1)	(2)	10/07/2023	Common Stock	3,539	0.0001	I	See footnote(3)
Call Options (obligation to sell)(1)	(2)	10/07/2023	Common Stock	1,723	0.0001	I	See footnote(4)
Call Options (obligation to sell)(1)	(2)	10/07/2023	Common Stock	1,914	0.0001	I	See footnote(5)

1. Name and Address of Reporting Person* Pontifax Management 4 G.P. (2015) Ltd. (Last) (First) (Middle) 14 SHENKAR STREET, BEIT OFEK (Street) HERZLIYA PITUACH L3 46140 (City) (State) (Zip)

1. Name and Address of Reporting Person* Pontifax (Israel) IV, L.P. (Last) (First) (Middle) 14 SHENKAR STREET, BEIT OFEK (Street) HERZLIYA PITUACH L3 46140 (City) (State) (Zip)

1. Name and Address of Reporting Person* Pontifax (Cayman) IV L.P. (Last) (First) (Middle) 14 SHENKAR STREET, BEIT OFEK (Street) HERZLIYA PITUACH L3 46140 (City) (State) (Zip)

1. Name and Address of Reporting Person* Pontifax (China) IV L.P. (Last) (First) (Middle) 14 SHENKAR STREET, BEIT OFEK (Street) HERZLIYA PITUACH L3 46140 (City) (State) (Zip)

1. Name and Address of Reporting Person* Pontifax Late Stage Fund L.P. (Last) (First) (Middle) 14 SHENKAR STREET, BEIT OFEK (Street) HERZLIYA PITUACH L3 46140 (City) (State) (Zip)

1. Name and Address of Reporting Person* Pontifax Late Stage GP Ltd. (Last) (First) (Middle) 14 SHENKAR STREET, BEIT OFEK (Street) HERZLIYA PITUACH L3 46140 (City) (State) (Zip)

Explanation of Responses:

1. This security was inadvertently omitted from the Original Form 3.

2. Fully vested and exercisable.

3. The securities are held by Pontifax (Israel) IV, L.P. ("Israel IV"). Pontifax Management 4 G.P. (2015) Ltd. ("Management 4") is the ultimate general partner of Israel IV. As a result Management 4 may be deemed to share voting and dispositive power with respect to the shares held by Israel IV. Management 4 disclaims beneficial ownership of such shares, except to the extent of its pecuniary interest therein, and the inclusion of the shares in this report shall not be deemed to be an admission of beneficial ownership of the reported shares for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise.

4. The securities are held by Pontifax (Cayman) IV, L.P. ("Cayman IV"). Management 4 is the ultimate general partner of Cayman IV. As a result Management 4 may be deemed to share voting and dispositive power with respect to the shares held by Cayman IV. Management 4 disclaims beneficial ownership of such shares, except to the extent of its pecuniary interest therein, and the inclusion of the shares in this report shall not be deemed to be an admission of beneficial ownership of the reported shares for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise.

5. The securities are held by Pontifax (China) IV, L.P. ("China IV"). Management 4 is the ultimate general partner of China IV. As a result Management 4 may be deemed to share voting and dispositive power with respect to the shares held by China IV. Management 4 disclaims beneficial ownership of such shares, except to the extent of its pecuniary interest therein, and the inclusion of the shares in this report shall not be deemed to be an admission of beneficial ownership of the reported shares for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise.

Remarks:

	/s/ Keith Regnante, Attorney-in-Fact for Pontifax Management 4 G.P. (2015) Ltd.	11/30/2022
	/s/ Keith Regnante, Attorney-in-Fact for Pontifax (Israel) IV L.P.	11/30/2022
	/s/ Keith Regnante, Attorney-in-Fact for Pontifax (Cayman) IV L.P.	11/30/2022
	/s/ Keith Regnante, Attorney-in-Fact for Pontifax (China) IV L.P.	11/30/2022
	/s/ Keith Regnante, Attorney-in-Fact for Pontifax Late Stage Fund, L.P.	11/30/2022
	/s/ Keith Regnante, Attorney-in-Fact for Pontifax Late Stage GP Ltd.	11/30/2022
	** 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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