Keros Therapeutics (KROS) director logs tender offer share sale in Form 4

Rhea-AI Filing Summary

Keros Therapeutics director Carl L. Gordon reported indirect sales of Keros Therapeutics, Inc. common stock in connection with the company’s completion of a cash tender offer. On 11/21/2025, 140,057 shares of common stock were disposed of at $17.75 per share, leaving 759,155 shares beneficially owned indirectly. On the same date, an additional 74,465 shares were disposed of at $17.75 per share, leaving 45,057 shares beneficially owned indirectly.

The shares are held through OrbiMed-affiliated investment entities, including OrbiMed Private Investments VII, LP and OrbiMed Genesis Master Fund, L.P. Various OrbiMed general partners and OrbiMed Advisors LLC may be deemed to share voting and investment power over these holdings, but each related entity and person, including the reporting person, disclaims beneficial ownership beyond any pecuniary interest.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider GORDON CARL L

Role Director

Type	Security	Shares	Price	Value
Disposition	Common Stock	140,057	$17.75	$2.49M
Disposition	Common Stock	74,465	$17.75	$1.32M

Holdings After Transaction: Common Stock — 759,155 shares (Indirect, See footnotes)

Footnotes (1)

1. Disposed of in connection with the Issuer's completion of a cash tender offer. These securities are held of record by OrbiMed Private Investments VII, LP ("OPI VII"). OrbiMed Capital GP VII LLC ("OrbiMed GP") is the general partner of OPI VII and OrbiMed Advisors LLC ("OrbiMed Advisors") is the managing member of OrbiMed GP. By virtue of such relationships, OrbiMed GP and OrbiMed Advisors may be deemed to have voting power and investment power over the securities held by OPI VII and as a result, may be deemed to have beneficial ownership over such securities. OrbiMed Advisors exercises voting and investment power through a management committee comprised of the Reporting Person, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the shares held by OPI VII. These securities are held of record by OrbiMed Genesis Master Fund, L.P. ("Genesis"). OrbiMed Genesis GP LLC ("Genesis GP") is the general partner of Genesis and OrbiMed Advisors is the managing member of Genesis GP. By virtue of such relationships, Genesis GP and OrbiMed Advisors may be deemed to have voting power and investment power over the securities held by Genesis and as a result, may be deemed to have beneficial ownership over such securities. OrbiMed Advisors exercises voting and investment power through a management committee comprised of the Reporting Person, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the shares held by Genesis. Each of the Reporting Person, OrbiMed Advisors, OrbiMed GP, and Genesis GP disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of his or its pecuniary interest therein, if any. This report shall not be deemed an admission that any such entity or person is a beneficial owner of such securities for purposes of Section 16 of the Exchange Act, or for any other purpose.

Form 4 Insider Transactions: What Each Field Means →

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

OMB APPROVAL

OMB Number:			3235-0287
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hours per response:			0.5

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

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

GORDON CARL L

(Last) (First) (Middle)

C/O KEROS THERAPEUTICS, INC.

1050 WALTHAM STREET, SUITE 302

(Street)

LEXINGTON MA 02421

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Keros Therapeutics, Inc. [ KROS ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
11/21/2025

4. 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 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)
			Code	V	Amount	(A) or (D)	Price
Common Stock	11/21/2025		D(1)		140,057	D	$17.75	759,155	I	See footnotes(2)(4)
Common Stock	11/21/2025		D(1)		74,465	D	$17.75	45,057	I	See footnotes(3)(4)

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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Disposed of in connection with the Issuer's completion of a cash tender offer.

2. These securities are held of record by OrbiMed Private Investments VII, LP ("OPI VII"). OrbiMed Capital GP VII LLC ("OrbiMed GP") is the general partner of OPI VII and OrbiMed Advisors LLC ("OrbiMed Advisors") is the managing member of OrbiMed GP. By virtue of such relationships, OrbiMed GP and OrbiMed Advisors may be deemed to have voting power and investment power over the securities held by OPI VII and as a result, may be deemed to have beneficial ownership over such securities. OrbiMed Advisors exercises voting and investment power through a management committee comprised of the Reporting Person, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the shares held by OPI VII.

3. These securities are held of record by OrbiMed Genesis Master Fund, L.P. ("Genesis"). OrbiMed Genesis GP LLC ("Genesis GP") is the general partner of Genesis and OrbiMed Advisors is the managing member of Genesis GP. By virtue of such relationships, Genesis GP and OrbiMed Advisors may be deemed to have voting power and investment power over the securities held by Genesis and as a result, may be deemed to have beneficial ownership over such securities. OrbiMed Advisors exercises voting and investment power through a management committee comprised of the Reporting Person, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the shares held by Genesis.

4. Each of the Reporting Person, OrbiMed Advisors, OrbiMed GP, and Genesis GP disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of his or its pecuniary interest therein, if any. This report shall not be deemed an admission that any such entity or person is a beneficial owner of such securities for purposes of Section 16 of the Exchange Act, or for any other purpose.

	/s/ Carl L. Gordon	12/18/2025
	** 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).
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.

FAQ

What insider transaction did Keros Therapeutics (KROS) report in this Form 4?

The filing reports that a director, through OrbiMed-affiliated entities, disposed of 140,057 and 74,465 shares of Keros Therapeutics, Inc. common stock on 11/21/2025 at $17.75 per share in connection with a cash tender offer.

Who is the reporting person in this Keros Therapeutics (KROS) Form 4?

The reporting person is Carl L. Gordon, who is identified as a director of Keros Therapeutics, Inc. and signed the report.

How many Keros Therapeutics (KROS) shares are beneficially owned after the reported transactions?

Following the reported tender offer transactions, the filing states that 759,155 shares and 45,057 shares of Keros Therapeutics, Inc. common stock are beneficially owned indirectly through OrbiMed-affiliated entities.

At what price were Keros Therapeutics (KROS) shares disposed of in the cash tender offer?

The reported dispositions of Keros Therapeutics, Inc. common stock on 11/21/2025 occurred at a price of $17.75 per share.

Which entities hold the Keros Therapeutics (KROS) shares referenced in this Form 4?

The filing explains that the shares are held of record by OrbiMed Private Investments VII, LP and OrbiMed Genesis Master Fund, L.P., with related control entities including OrbiMed Capital GP VII LLC, OrbiMed Genesis GP LLC, and OrbiMed Advisors LLC.

Do OrbiMed entities and the director claim full beneficial ownership of these Keros Therapeutics (KROS) shares?

No. The filing states that each of the reporting person and the OrbiMed entities disclaims beneficial ownership of the reported securities except to the extent of any pecuniary interest.

What triggered the insider share disposition for Keros Therapeutics (KROS) in this report?

The explanation states that the shares were disposed of in connection with Keros Therapeutics, Inc.'s completion of a cash tender offer.