RA CAPITAL MANAGEMENT, L.P. - 28 Sep 2026 Form 4 Insider Report for Climb Bio, Inc. (CLYM)

Reporting relationship: Director, 10%+ Owner
Issuer ticker: CLYM
Reported as of: 28 Sep 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 30 Sep 2026, 16:55:47 UTC
Prior SEC filing: 21 Sep 2026
Next SEC filing: 05 Oct 2026
Source filing: View source filing
Reporting owner signature: /s/ Peter Kolchinsky, Manager of RA Capital Management, L.P.

Filing notes and source

Key filing fact

RA CAPITAL MANAGEMENT, L.P. filed Form 4 for Climb Bio, Inc. (CLYM) on 30 Sep 2026.

Key facts

This page summarizes RA CAPITAL MANAGEMENT, L.P.'s Form 4 filing for Climb Bio, Inc. (CLYM).
7 reported transactions and 21 derivative rows are listed below.
Accepted by SEC: 30 Sep 2026, 16:55.

Change

Previous filing in this sequence was filed on 21 Sep 2026.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (7)

CIK 0001346824 Primary reporting owner

RA CAPITAL MANAGEMENT, L.P.

Relationship: Director, 10%+ Owner
Address: 200 BERKELEY STREET, 18TH FLOOR, BOSTON
Signature: /s/ Peter Kolchinsky, Manager of RA Capital Management, L.P.
Signature date: 30 Sep 2026

CIK 0001315082

RA Capital Healthcare Fund LP

Relationship: Director, 10%+ Owner
Address: 200 BERKELEY STREET, 18TH FLOOR, BOSTON
Signature: /s/ Peter Kolchinsky, Manager of RA Capital Healthcare Fund GP, LLC the General Partner of RA Capital Healthcare Fund, L.P.
Signature date: 30 Sep 2026

CIK 0001780117

RA Capital Nexus Fund, L.P.

Relationship: Director
Address: 200 BERKELEY STREET, 18TH FLOOR, BOSTON
Signature: /s/ Peter Kolchinsky, Manager of RA Capital Nexus Fund GP, LLC, the General Partner of RA Capital Nexus Fund, L.P.
Signature date: 30 Sep 2026

CIK 0001825376

RA Capital Nexus Fund II, L.P.

Relationship: Director
Address: 200 BERKELEY STREET, 18TH FLOOR, BOSTON
Signature: /s/ Peter Kolchinsky, Manager of RA Capital Nexus Fund II GP, LLC, the General Partner of RA Capital Nexus Fund II, L.P.
Signature date: 30 Sep 2026

CIK 0001883840

RA Capital Nexus Fund III, L.P.

Relationship: Director
Address: 200 BERKELEY STREET, 18TH FLOOR, BOSTON
Signature: /s/ Peter Kolchinsky, Manager of RA Capital Nexus Fund III GP, LLC, the General Partner of RA Capital Nexus Fund III, L.P.
Signature date: 30 Sep 2026

CIK 0001384859

Kolchinsky Peter

Relationship: Director, 10%+ Owner
Address: C/O RA CAPITAL MANAGEMENT, L.P., 200 BERKELEY STREET, 18TH FLOOR, BOSTON
Signature: /s/ Peter Kolchinsky, individually
Signature date: 30 Sep 2026

CIK 0001619841

Shah Rajeev M.

Relationship: Director, 10%+ Owner
Address: C/O RA CAPITAL MANAGEMENT, L.P., 200 BERKELEY STREET, 18TH FLOOR, BOSTON
Signature: /s/ Rajeev Shah, individually
Signature date: 30 Sep 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %
Price: $3.46^*
Shares after: 10,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %
Price: $3.46^*
Shares after: 10,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %
Price: $3.46^*
Shares after: 10,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %
Price: $3.46^*
Shares after: 10,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %
Price: $3.46^*
Shares after: 10,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %
Price: $3.46^*
Shares after: 10,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %
Price: $3.46^*
Shares after: 10,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +100%
Price: $3.00^*
Shares after: 20,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +100%
Price: $3.00^*
Shares after: 20,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +100%
Price: $3.00^*
Shares after: 20,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +100%
Price: $3.00^*
Shares after: 20,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +100%
Price: $3.00^*
Shares after: 20,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +100%
Price: $3.00^*
Shares after: 20,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +100%
Price: $3.00^*
Shares after: 20,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +50%
Price: $7.89^*
Shares after: 30,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +50%
Price: $7.89^*
Shares after: 30,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +50%
Price: $7.89^*
Shares after: 30,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +50%
Price: $7.89^*
Shares after: 30,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +50%
Price: $7.89^*
Shares after: 30,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +50%
Price: $7.89^*
Shares after: 30,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +50%
Price: $7.89^*
Shares after: 30,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +40,000
Change %: +133%
Price: $1.29^*
Shares after: 70,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +40,000
Change %: +133%
Price: $1.29^*
Shares after: 70,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +40,000
Change %: +133%
Price: $1.29^*
Shares after: 70,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +40,000
Change %: +133%
Price: $1.29^*
Shares after: 70,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +40,000
Change %: +133%
Price: $1.29^*
Shares after: 70,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +40,000
Change %: +133%
Price: $1.29^*
Shares after: 70,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM transaction

Common Stock

Options Exercise

Transaction value
Shares: +40,000
Change %: +133%
Price: $1.29^*
Shares after: 70,000
Date: 28 Sep 2026
Ownership: See footnotes
Footnotes: F1, F2

CLYM holding