Fairmount Funds Management LLC - 23 Jun 2026 Form 4 Insider Report for Spyre Therapeutics, Inc. (SYRE)

Reporting relationship: Director
Issuer ticker: SYRE
Reported as of: 23 Jun 2026
Net transaction value: -$399,658,667
SEC form: 4
Accepted by SEC: 23 Jun 2026, 21:56:26 UTC
Prior SEC filing: 11 Jun 2026
Next 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 Spyre Therapeutics, Inc. (SYRE) on 23 Jun 2026.

Key facts

This page summarizes Fairmount Funds Management LLC's Form 4 filing for Spyre Therapeutics, Inc. (SYRE).
3 reported transactions and 8 derivative rows are listed below.
Accepted by SEC: 23 Jun 2026, 21:56.

Change

Previous filing in this sequence was filed on 11 Jun 2026.
Current net transaction value: -$399,658,667.

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
Address: 200 BARR HARBOR DRIVE, SUITE 400, WEST CONSHOHOCKEN
Signature: /s/ Tomas Kiselak, Managing Member of Fairmount Funds Management LLC
Signature date: 23 Jun 2026

CIK 0001769651

Fairmount Healthcare Fund II L.P.

Relationship: Director
Address: 200 BARR HARBOR DRIVE, SUITE 400, WEST CONSHOHOCKEN
Signature: /s/ Tomas Kiselak, Managing Member of Fairmount Healthcare Fund II, L.P.
Signature date: 23 Jun 2026

CIK 0001830177

Kiselak Tomas

Relationship: Director
Address: 200 BARR HARBOR DRIVE, SUITE 400, WEST CONSHOHOCKEN
Signature: /s/ Tomas Kiselak
Signature date: 23 Jun 2026

CIK 0001663607

Harwin Peter Evan

Relationship: Director
Address: 200 BARR HARBOR DRIVE, SUITE 400, WEST CONSHOHOCKEN
Signature: s/ Peter Harwin
Signature date: 23 Jun 2026

Reported non-derivative transactions

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

SYRE transaction

Common Stock

Conversion of derivative security

Transaction value
Shares: +666,680
Change %: +17%
Price
Shares after: 4,684,781
Date: 23 Jun 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F1, F2

SYRE transaction

Common Stock

Conversion of derivative security

Transaction value
Shares: +666,680
Change %: +17%
Price
Shares after: 4,684,781
Date: 23 Jun 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F1, F2

SYRE transaction

Common Stock

Conversion of derivative security

Transaction value
Shares: +666,680
Change %: +17%
Price
Shares after: 4,684,781
Date: 23 Jun 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F1, F2

SYRE transaction

Common Stock

Conversion of derivative security

Transaction value
Shares: +666,680
Change %: +17%
Price
Shares after: 4,684,781
Date: 23 Jun 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F1, F2

SYRE transaction

Common Stock

Sale

Transaction value: $399,658,667
Shares: -4,684,781
Change %: -100%
Price: $85.31
Shares after: 0
Date: 23 Jun 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F2

SYRE transaction

Common Stock

Sale

Transaction value: $399,658,667
Shares: -4,684,781
Change %: -100%
Price: $85.31
Shares after: 0
Date: 23 Jun 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F2

SYRE transaction

Common Stock

Sale

Transaction value: $399,658,667
Shares: -4,684,781
Change %: -100%
Price: $85.31
Shares after: 0
Date: 23 Jun 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F2

SYRE transaction

Common Stock

Sale

Transaction value: $399,658,667
Shares: -4,684,781
Change %: -100%
Price: $85.31
Shares after: 0
Date: 23 Jun 2026
Ownership: By Fairmount Healthcare Fund II L.P.
Footnotes: F2

SYRE holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 406,038
Date: 23 Jun 2026
Ownership: By Tomas Kiselak

SYRE holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 406,038
Date: 23 Jun 2026
Ownership: By Tomas Kiselak

SYRE holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 406,038
Date: 23 Jun 2026
Ownership: By Tomas Kiselak

SYRE holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 406,038
Date: 23 Jun 2026
Ownership: By Tomas Kiselak

SYRE holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 406,038
Date: 23 Jun 2026
Ownership: By Peter Harwin

SYRE holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 406,038
Date: 23 Jun 2026
Ownership: By Peter Harwin

SYRE holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 406,038
Date: 23 Jun 2026
Ownership: By Peter Harwin

SYRE holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 406,038
Date: 23 Jun 2026
Ownership: By Peter Harwin

Reported derivative securities

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

SYRE transaction Derivative

Series B Preferred Stock

Conversion of derivative security

Transaction value
Shares: -16,667
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 23 Jun 2026
Ownership: Fairmount Healthcare Fund II LP
Underlying class: Common Stock
Underlying amount: 666,680
Exercise price
Footnotes: F1, F2

SYRE transaction Derivative

Series B Preferred Stock

Conversion of derivative security

Transaction value
Shares: -16,667
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 23 Jun 2026
Ownership: Fairmount Healthcare Fund II LP
Underlying class: Common Stock
Underlying amount: 666,680
Exercise price
Footnotes: F1, F2

SYRE transaction Derivative

Series B Preferred Stock

Conversion of derivative security

Transaction value
Shares: -16,667
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 23 Jun 2026
Ownership: Fairmount Healthcare Fund II LP
Underlying class: Common Stock
Underlying amount: 666,680
Exercise price
Footnotes: F1, F2

SYRE transaction Derivative

Series B Preferred Stock

Conversion of derivative security

Transaction value
Shares: -16,667
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 23 Jun 2026
Ownership: Fairmount Healthcare Fund II LP
Underlying class: Common Stock
Underlying amount: 666,680
Exercise price
Footnotes: F1, F2

SYRE holding Derivative

Series A Preferred Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 346,045
Date: 23 Jun 2026
Ownership: Fairmount Healthcare Fund II LP
Underlying class: Common Stock
Underlying amount: 13,841,800
Exercise price
Footnotes: F2, F3

SYRE holding Derivative

Series A Preferred Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 346,045
Date: 23 Jun 2026
Ownership: Fairmount Healthcare Fund II LP
Underlying class: Common Stock
Underlying amount: 13,841,800
Exercise price
Footnotes: F2, F3

SYRE holding Derivative

Series A Preferred Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 346,045
Date: 23 Jun 2026
Ownership: Fairmount Healthcare Fund II LP
Underlying class: Common Stock
Underlying amount: 13,841,800
Exercise price
Footnotes: F2, F3

SYRE holding Derivative

Series A Preferred Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 346,045
Date: 23 Jun 2026
Ownership: Fairmount Healthcare Fund II LP
Underlying class: Common Stock
Underlying amount: 13,841,800
Exercise price
Footnotes: F2, F3

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

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

Each share of Series B Preferred Stock is convertible at the option of the holder into 40 shares of Common Stock, subject to certain beneficial ownership limitations, including that a holder of Series B Preferred Stock is prohibited from converting shares of Series B Preferred Stock into shares of Common Stock if, as a result of such conversion, such holder, together with its affiliates, would beneficially own more than 9.99% of the total number of shares of Common Stock issued and outstanding immediately after giving effect to such conversion. On June 23, 2026, the Reporting Persons converted 16,667 shares of Series B Preferred Stock into 666,680 shares of Common Stock for no cash consideration, in accordance with the Certificate of Designations for the Series B Convertible Preferred Stock.

Footnote F2

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 F3

Each share of Series A Preferred Stock is convertible at the option of the holder into 40 shares of Common Stock, subject to certain beneficial ownership limitations, including that a holder of Series A Preferred Stock is prohibited from converting shares of Series A Preferred Stock into shares of Common Stock if, as a result of such conversion, such holder, together with its affiliates, would beneficially own more than 9.99% of the total number of shares of Common Stock issued and outstanding immediately after giving effect to such conversion.

SEC remarks

The Reporting Persons may each be deemed a director by deputization of Issuer by virtue of the fact that Tomas Kiselak serves on the board of directors of Issuer and is also a Managing Member of Fairmount Funds Management LLC.