Fairmount Funds Management LLC - 16 Jul 2026 Form 4 Insider Report for CRESCENT BIOPHARMA, INC. (CBIO)

Reporting relationship: Director, 10%+ Owner
Issuer ticker: CBIO
Reported as of: 16 Jul 2026
Net transaction value: +$20,000,006
SEC form: 4
Accepted by SEC: 20 Jul 2026, 17:30:09 UTC
Prior SEC filing: 01 Jul 2026
Source filing: View source filing
Reporting owner signature: /s/ Tomas Kiselak, Managing Member of Fairmount Funds Management LLC

Key filing fact

Fairmount Funds Management LLC filed Form 4 for CRESCENT BIOPHARMA, INC. (CBIO) on 20 Jul 2026.

Key facts

This page summarizes Fairmount Funds Management LLC's Form 4 filing for CRESCENT BIOPHARMA, INC. (CBIO).
2 reported transactions and 4 derivative rows are listed below.
Accepted by SEC: 20 Jul 2026, 17:30.

Change

Previous filing in this sequence was filed on 01 Jul 2026.
Current net transaction value: +$20,000,006.

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 (4)

CIK 0001802528 Primary reporting owner

Fairmount Funds Management LLC

Relationship: Director, 10%+ Owner
Address: 200 BARR HARBOR DRIVE, SUITE 400, WEST CONSHOHOCKEN
Signature: /s/ Tomas Kiselak, Managing Member of Fairmount Funds Management LLC
Signature date: 20 Jul 2026

CIK 0001769651

Fairmount Healthcare Fund II L.P.

Relationship: Director, 10%+ Owner
Address: 200 BARR HARBOR DRIVE, SUITE 400, WEST CONSHOHOCKEN
Signature: /s/ Tomas Kiselak, Managing Member of Fairmount Healthcare Fund II, L.P.
Signature date: 20 Jul 2026

CIK 0001830177

Kiselak Tomas

Relationship: Director, 10%+ Owner
Address: 200 BARR HARBOR DRIVE, SUITE 400, WEST CONSHOHOCKEN
Signature: /s/ Tomas Kiselak
Signature date: 20 Jul 2026

CIK 0001663607

Harwin Peter Evan

Relationship: Director, 10%+ Owner
Address: 200 BARR HARBOR DRIVE, SUITE 400, WEST CONSHOHOCKEN
Signature: /s/ Peter Harwin
Signature date: 20 Jul 2026

Reported non-derivative transactions

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

CBIO transaction

Ordinary Shares

Purchase

Transaction value: $12,375,025
Shares: +853,450
Change %: +31%
Price: $14.50
Shares after: 3,601,316
Date: 16 Jul 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F1

CBIO transaction

Ordinary Shares

Purchase

Transaction value: $12,375,025
Shares: +853,450
Change %: +31%
Price: $14.50
Shares after: 3,601,316
Date: 16 Jul 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F1

CBIO transaction

Ordinary Shares

Purchase

Transaction value: $12,375,025
Shares: +853,450
Change %: +31%
Price: $14.50
Shares after: 3,601,316
Date: 16 Jul 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F1

CBIO transaction

Ordinary Shares

Purchase

Transaction value: $12,375,025
Shares: +853,450
Change %: +31%
Price: $14.50
Shares after: 3,601,316
Date: 16 Jul 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F1

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

CBIO transaction Derivative

Pre-Funded Warrant (Right to Buy)

Purchase

Transaction value: $7,624,981
Shares: +525,897
Change %: +30%
Price: $14.50
Shares after: 2,294,037
Date: 16 Jul 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Underlying class: Ordinary Shares
Underlying amount: 525,897
Exercise price: $0.001000
Footnotes: F1, F2

CBIO transaction Derivative

Pre-Funded Warrant (Right to Buy)

Purchase

Transaction value: $7,624,981
Shares: +525,897
Change %: +30%
Price: $14.50
Shares after: 2,294,037
Date: 16 Jul 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Underlying class: Ordinary Shares
Underlying amount: 525,897
Exercise price: $0.001000
Footnotes: F1, F2

CBIO transaction Derivative

Pre-Funded Warrant (Right to Buy)

Purchase

Transaction value: $7,624,981
Shares: +525,897
Change %: +30%
Price: $14.50
Shares after: 2,294,037
Date: 16 Jul 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Underlying class: Ordinary Shares
Underlying amount: 525,897
Exercise price: $0.001000
Footnotes: F1, F2

CBIO transaction Derivative

Pre-Funded Warrant (Right to Buy)

Purchase

Transaction value: $7,624,981
Shares: +525,897
Change %: +30%
Price: $14.50
Shares after: 2,294,037
Date: 16 Jul 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Underlying class: Ordinary Shares
Underlying amount: 525,897
Exercise price: $0.001000
Footnotes: F1, F2

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 2 footnotes

Footnote F1

Fairmount Funds Management LLC ("Fairmount") is the investment manager for Fairmount Healthcare Fund II L.P. The managers of Fairmount are Peter Harwin and Tomas Kiselak. Fairmount, Mr. Harwin, and Mr. Kiselak disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

Footnote F2

The Pre-Funded Warrants have no expiration date and are exercisable at any time after the date of issuance. A holder of Pre-Funded Warrants may not exercise the Pre-Funded Warrant if the holder, together with its affiliates, would beneficially own more than 9.99% of the number of outstanding shares of common stock of the Issuer immediately after giving effect to such exercise.

SEC remarks

Fairmount may be deemed a director by deputization of Issuer by virtue of the fact that Peter Harwin serves on the board of directors of the Issuer and is a manager of Fairmount.