Jean Jacques Bienaime - 09 Mar 2026 Form 4 Insider Report for Keros Therapeutics, Inc. (KROS)

Role: Director
Signature: /s/ Esther Cho, Attorney-in-Fact
Issuer symbol: KROS
Transactions as of: 09 Mar 2026
Net transactions value: +$22,420
Form type: 4
Filing time: 11 Mar 2026, 16:33:59 UTC
Previous filing: 12 Jun 2025
Next filing: 12 Mar 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
BIENAIME JEAN JACQUES	Director	C/O KEROS THERAPEUTICS, INC., 1050 WALTHAM STREET, SUITE 302, LEXINGTON	/s/ Esther Cho, Attorney-in-Fact	11 Mar 2026	0001221590

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	KROS	Common Stock	Purchase	$22,420	+2,000	+37%	$11.21	7,450	09 Mar 2026	Direct	F1, F2

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Buy Plan / Sale Plan: These are also open market purchases/sales of shares, but in this case the transaction is part of a trading plan. Rule 10b5-1 allows insiders to setup a trading plan to buy/sell stocks over a certain period of time. Since the purchases/sales are predetermined, this protects the insiders from violating insider trading law.

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).

Explanation of Responses:

Id	Content
F1	Shares were purchased pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 5, 2025.
F2	The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $10.98 to $11.48 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote.

Content

Shares were purchased pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 5, 2025.

The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $10.98 to $11.48 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote.