[4] – Schneeberger Daniel (CIK 0001861120)

Rhea-AI Filing Summary

Keros Therapeutics (KROS): Section 16 filing reports insider sales. On 10/15/2025, reporting persons linked to ADAR1 disclosed sales of Keros common stock at $17.75 per share. The transactions were reported as indirect holdings through affiliated entities.

Reported sales included 4,391,237 shares by ADAR1 Partners, LP; 254,669 shares by ADAR1 SPV I, LP; and 743,358 shares by Spearhead Insurance Solutions IDF, LLC. For each line item, the amount of securities beneficially owned following the transactions was listed as 0, with ownership form marked as indirect.

The filing notes that ADAR1 Capital Management, LLC (investment manager/sub‑advisor), ADAR1 Capital Management GP, LLC (general partner), and Daniel Schneeberger (manager) may be deemed to indirectly beneficially own the securities, and each disclaims beneficial ownership except to the extent of pecuniary interest.

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Form 4 shows indirect sales at $17.75; post-transaction lines show 0 held.

This Section 16 report lists sales of Keros common stock on 10/15/2025 at $17.75 per share by entities associated with ADAR1. The amounts are reported by holder: ADAR1 Partners, LP 4,391,237; ADAR1 SPV I, LP 254,669; Spearhead Insurance Solutions IDF, LLC 743,358, each shown as indirectly held.

For each entry, the amount of securities beneficially owned following the transactions is stated as 0, indicating no remaining reported holdings for those line items. The filing includes standard Section 16 disclaimers that the reporting persons may be deemed to beneficially own the securities through management and partnership roles, while disclaiming beneficial ownership except to pecuniary interest.

Actual market impact depends on transaction execution details and broader trading activity; the filing documents the reported sales and indirect ownership structure.

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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X

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^*

ADAR1 Capital Management, LLC

(Last) (First) (Middle)

3503 WILD CHERRY DRIVE

BUILDING 9

(Street)

AUSTIN TX 78738

(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)

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

3. Date of Earliest Transaction (Month/Day/Year)
10/15/2025

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)
			Code	V	Amount	(A) or (D)	Price
Common Stock	10/15/2025		S		4,391,237	D	$17.75	0	I	By ADAR1 Partners, LP(1)(2)
Common Stock	10/15/2025		S		254,669	D	$17.75	0	I	By ADAR1 SPVI, LP(1)(2)
Common Stock	10/15/2025		S		743,358	D	$17.75	0	I	By Spearhead Insurance Solutions IDF, LLC(1)(2)

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

1. Name and Address of Reporting Person^*

ADAR1 Capital Management, LLC

(Last) (First) (Middle)

3503 WILD CHERRY DRIVE

BUILDING 9

(Street)

AUSTIN TX 78738

(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^*

ADAR1 Partners, LP

(Last) (First) (Middle)

3503 WILD CHERRY DRIVE

BUILDING 9

(Street)

AUSTIN TX 78738

(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^*

ADAR1 Capital Management GP, LLC

(Last) (First) (Middle)

3503 WILD CHERRY DRIVE

BUILDING 9

(Street)

AUSTIN TX 78738

(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^*

Schneeberger Daniel

(Last) (First) (Middle)

3503 WILD CHERRY DRIVE

BUILDING 9

(Street)

AUSTIN TX 78738

(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. The securities to which this filing relates are held directly by ADAR1 Partners, LP, ADAR1 SPV I, LP and Spearhead Insurance Solutions IDF, LLC. As the investment manager of ADAR1 Partners, LP and ADAR1 SPV I, LP and as the sub-advisor of Spearhead Insurance Solutions IDF, LLC, ADAR1 Capital Management, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, ADAR1 SPV I, LP and Spearhead Insurance Solutions IDF, LLC. As the general partner of ADAR1 Partners, LP and ADAR1 SPV I, LP, ADAR1 Capital Management GP, LLC may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP and ADAR1 SPV I, LP. As the manager of ADAR1 Capital Management, LLC and ADAR1 Capital Management GP, LLC, Daniel Schneeberger may be deemed to indirectly beneficially own securities held by ADAR1 Partners, LP, Spearhead Insurance Solutions IDF, LLC, and ADAR1 SPV I, LP.

2. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

	ADAR1 Capital Management, LLC By: Daniel Schneeberger, Manager /s/ Daniel Schneeberger	10/15/2025
	ADAR1 Partners, LP By: Daniel Schneeberger, Manager /s/ Daniel Schneeberger	10/15/2025
	ADAR1 Capital Management GP, LLC By: Daniel Schneeberger, Manager /s/ Daniel Schneeberger	10/15/2025
	Daniel Schneeberger, Manager /s/ Daniel Schneeberger	10/15/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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