Comparable stake leader
Fairmount Funds Management LLC
SEC ownership of Spyre Therapeutics, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001636282.
Disclosed value leader
Fairmount Funds Management LLC
Comparable rows
50/50
Latest evidence
23 Jun 2026
- Public ticker
- SYRE on Nasdaq
- Parsed ownership sources
-
13D/G, 3/4/5, and 13F
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
- Largest SEC-reported holder
-
Fairmount Funds Management LLC
Ranking: Comparable ownership first, then disclosed value
- Comparable ownership rows
-
50 of 50
Meaning: Rows with safely comparable ownership %
- Latest 13D/G holder
-
Fairmount Funds Management LLC
Source: Latest parsed Schedule 13D/G stake
- Latest parsed ownership date
-
23 Jun 2026
Freshness: Most recent filing date in this holder set
- Issuer CIK
- 0001636282
- Issuer location
- Waltham, MA
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
3 signals
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of Spyre Therapeutics, Inc. (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
Fairmount Funds Managemen...
Disclosed value leader
Fairmount Funds Managemen...
Comparable rows
50/50
Latest evidence
23 Jun 2026
13D/G
3/4/5
13F
Lead comparable stake: 10%
13D/G row: Fairmount Funds Management LLC
Showing 1-8 of 50 holder rows.
Quick read
Fairmount Funds Management LLC leads the comparable SEC ownership view at 10%.
50 of 50 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Open SEC evidence
Opens Fairmount Funds Management LLC's linked filing trail.
Comparable ownership
Top 5
Fairmount Funds Management LLC
10%
BlackRock, Inc.
6.6%
RTW INVESTMENTS, LP
6.2%
PERCEPTIVE ADVISORS LLC
5%
Venrock Healthcare Capital Partne...
4.6%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 50 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Fairmount Funds Management LLC |
13D/G
3/4/5
13F
Peter Evan Harwin · Director · Company
|
10%
|
$697,101,864
9,667,201 shares
|
+$46,907,483 | 23 Jun 2026 |
| BlackRock, Inc. |
13F
13D/G
Company
|
6.6%
from 13D/G
|
$278,490,385
5,521,221 shares
|
— | 31 Mar 2026 |
| RTW INVESTMENTS, LP |
13F
13D/G
Company
|
6.2%
from 13D/G
|
$210,435,478
4,171,996 shares
|
— | 31 Mar 2026 |
| PERCEPTIVE ADVISORS LLC |
13D/G
13F
Company
|
5%
|
$217,875,378
4,319,496 shares
|
+$88,006,350 | 15 Apr 2026 |
| Venrock Healthcare Capital Partners III, L.P. |
13D/G
|
4.6%
|
$40,335,429
2,685,448 shares
|
$0 | 31 Dec 2024 |
| TANG CAPITAL MANAGEMENT LLC |
13F
13D/G
Company
|
2.4%
from 13D/G
|
$95,442,568
1,892,200 shares
|
— | 31 Mar 2026 |
| FMR LLC |
13F
Company
|
12%
|
$594,234,851
11,781,024 shares
|
— | 31 Mar 2026 |
| Venrock Adviser, LLC |
13F
Company
|
3.8%
|
$185,893,997
3,685,448 shares
|
— | 31 Mar 2026 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
Forms 3/4/5 flow
Insider trading overview
Net insider flow leans to selling over the last 12 months. Net value: -$1,625,355,058.
Buys
$0
Insiders: 0
Sells
$1,625,355,058
Insiders: 8
Net
-$1,625,355,058
Shares: -19,178,010
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 0
Shares: 19,178,010
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 18,915,791 | $0 | $1,612,812,398 | -$1,612,812,398 |
| 3-6 | 0 | 168,791 | $0 | $10,297,753 | -$10,297,753 |
| 6-9 | 0 | 75,000 | $0 | $1,945,267 | -$1,945,267 |
| 9-12 | 0 | 18,428 | $0 | $299,639 | -$299,639 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-20 of 30 reporting-owner rows connected to Spyre Therapeutics, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
30
Largest Forms 3/4/5 holder
Cameron Turtle
Net 12M change
-$1,625,355,057
Latest report
01 Jul 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Cameron Turtle | Chief Executive Officer, Director | $51,793,631 | -$7,252,430 | -12% | Filing P/S | 01 Jul 2026 |
| Fairmount Funds Management LLC | Director | $40,961,112 | -$399,658,667 | -91% | Mixed | 23 Jun 2026 |
| Fairmount Healthcare Fund II L.P. | Director | $40,961,112 | -$399,658,667 | -91% | Mixed | 23 Jun 2026 |
| Peter Evan Harwin | Director | $40,961,112 | -$399,658,667 | -91% | Mixed | 23 Jun 2026 |
| Tomas Kiselak | Director | $40,961,112 | -$399,658,667 | -91% | Mixed | 23 Jun 2026 |
| Scott L. Burrows | Chief Financial Officer | $8,659,729 | -$4,161,437 | -32% | Filing P/S | 01 Jul 2026 |
| Michael Thomas Henderson | Director | $6,860,600 | -$7,952,050 | -54% | Filing P/S | 22 Jun 2026 |
| Jeffrey W. Albers | Director | $1,005,838 | Filing P/S | 27 May 2026 | ||
| Anthony G. Quinn | President & CEO, Director | $579,952 | Mixed | 16 Mar 2022 | ||
| Marcio Souza | Director | $63,900 | Mixed | 25 Aug 2022 | ||
| Sheldon Sloan | Chief Medical Officer | $0 | -$7,354,472 | -100% | Mixed | 01 Jul 2026 |
| Jonathan Alspaugh | President and CFO | Mixed | 22 Jun 2023 | |||
| Hunter C. Smith | Director | Mixed | 22 Jun 2023 | |||
| Jr. Michael Conick Hanley | Chief Business Officer | Mixed | 23 Feb 2023 | |||
| Leslie Sloan | Chief Operating Officer | Mixed | 23 Aug 2022 | |||
| Sandesh Mahatme | Director | Mixed | 07 Jun 2022 | |||
| Ivana Magovcevic-Liebisch | Director | Mixed | 22 Jun 2023 | |||
| Steven Weber | VP, Controller&Princ Acctg Off | Mixed | 17 Feb 2022 | |||
| Bryan Lawlis V | Director | Mixed | 07 Jun 2022 | |||
| James Paul Kastenmayer | General Counsel | Mixed | 23 Feb 2023 |
Recent insider transactions for Spyre Therapeutics, Inc.
Showing up to 300 recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | SEC-reported value | SEC-reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| Scott L. Burrows | SYRE | Common Stock | Sale | -7.11% | $658,040 | $87.74 | -7,500 | 97,994 | 01 Jul 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Options Exercise | 7.65% | 7,500 | 105,494 | 01 Jul 2026 | Direct | ||
| Scott L. Burrows | SYRE | Stock Option (Right to Buy) | Options Exercise | -2.08% | -7,500 | 352,357 | 01 Jul 2026 | Direct | ||
| Sheldon Sloan | SYRE | Common Stock | Sale | -100% | $730,896 | $87.70 | -8,334 | 0 | 01 Jul 2026 | Direct |
| Sheldon Sloan | SYRE | Common Stock | Options Exercise | 8,334 | 8,334 | 01 Jul 2026 | Direct | |||
| Sheldon Sloan | SYRE | Stock Option (Right to Buy) | Options Exercise | -2.66% | -8,334 | 305,000 | 01 Jul 2026 | Direct | ||
| Cameron Turtle | SYRE | Common Stock | Sale | -2.51% | $1,315,346 | $87.69 | -15,000 | 582,540 | 01 Jul 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Sale | -13.3% | $1,307,000 | $87.13 | -15,000 | 97,994 | 25 Jun 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Options Exercise | 15.3% | 15,000 | 112,994 | 25 Jun 2026 | Direct | ||
| Scott L. Burrows | SYRE | Stock Option (Right to Buy) | Options Exercise | -4% | -15,000 | 359,857 | 25 Jun 2026 | Direct | ||
| Fairmount Funds Management LLC | SYRE | Common Stock | Sale | -100% | $399,658,667 | $85.31 | -4,684,781 | 0 | 23 Jun 2026 | By Fairmount Healthcare Fund II L.P. |
| Fairmount Funds Management LLC | SYRE | Common Stock | Sale | -100% | $399,658,667 | $85.31 | -4,684,781 | 0 | 23 Jun 2026 | By Fairmount Healthcare Fund II L.P. |
| Fairmount Funds Management LLC | SYRE | Common Stock | Sale | -100% | $399,658,667 | $85.31 | -4,684,781 | 0 | 23 Jun 2026 | By Fairmount Healthcare Fund II L.P. |
| Fairmount Funds Management LLC | SYRE | Common Stock | Sale | -100% | $399,658,667 | $85.31 | -4,684,781 | 0 | 23 Jun 2026 | By Fairmount Healthcare Fund II L.P. |
| Fairmount Funds Management LLC | SYRE | Common Stock | Conversion of derivative security | 16.6% | 666,680 | 4,684,781 | 23 Jun 2026 | By Fairmount Healthcare Fund II L.P. | ||
| Fairmount Funds Management LLC | SYRE | Common Stock | Conversion of derivative security | 16.6% | 666,680 | 4,684,781 | 23 Jun 2026 | By Fairmount Healthcare Fund II L.P. | ||
| Fairmount Funds Management LLC | SYRE | Common Stock | Conversion of derivative security | 16.6% | 666,680 | 4,684,781 | 23 Jun 2026 | By Fairmount Healthcare Fund II L.P. | ||
| Fairmount Funds Management LLC | SYRE | Common Stock | Conversion of derivative security | 16.6% | 666,680 | 4,684,781 | 23 Jun 2026 | By Fairmount Healthcare Fund II L.P. | ||
| Fairmount Funds Management LLC | SYRE | Series B Preferred Stock | Conversion of derivative security | -100% | -16,667 | 0 | 23 Jun 2026 | Fairmount Healthcare Fund II LP | ||
| Fairmount Funds Management LLC | SYRE | Series B Preferred Stock | Conversion of derivative security | -100% | -16,667 | 0 | 23 Jun 2026 | Fairmount Healthcare Fund II LP | ||
| Fairmount Funds Management LLC | SYRE | Series B Preferred Stock | Conversion of derivative security | -100% | -16,667 | 0 | 23 Jun 2026 | Fairmount Healthcare Fund II LP | ||
| Fairmount Funds Management LLC | SYRE | Series B Preferred Stock | Conversion of derivative security | -100% | -16,667 | 0 | 23 Jun 2026 | Fairmount Healthcare Fund II LP | ||
| Michael Thomas Henderson | SYRE | Common Stock | Sale | -22.6% | $2,000,000 | $100.00 | -20,000 | 68,606 | 22 Jun 2026 | Direct |
| Sheldon Sloan | SYRE | Common Stock | Sale | -100% | $624,975 | $75.00 | -8,333 | 0 | 03 Jun 2026 | Direct |
| Sheldon Sloan | SYRE | Common Stock | Options Exercise | 8,333 | 8,333 | 03 Jun 2026 | Direct | |||
| Sheldon Sloan | SYRE | Stock Option (Right to Buy) | Options Exercise | -2.59% | -8,333 | 313,334 | 03 Jun 2026 | Direct | ||
| Cameron Turtle | SYRE | Common Stock | Sale | -2.45% | $1,056,486 | $70.43 | -15,000 | 597,540 | 01 Jun 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Sale | -7.11% | $532,937 | $71.06 | -7,500 | 97,994 | 01 Jun 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Options Exercise | 7.65% | 7,500 | 105,494 | 01 Jun 2026 | Direct | ||
| Scott L. Burrows | SYRE | Stock Option (Right to Buy) | Options Exercise | -1.96% | -7,500 | 374,857 | 01 Jun 2026 | Direct | ||
| Fairmount Funds Management LLC | SYRE | Stock Option (Right to Buy) | Award | 8,026 | 8,026 | 27 May 2026 | By Tomas Kiselak | |||
| Fairmount Funds Management LLC | SYRE | Stock Option (Right to Buy) | Award | 8,026 | 8,026 | 27 May 2026 | By Tomas Kiselak | |||
| Fairmount Funds Management LLC | SYRE | Stock Option (Right to Buy) | Award | 8,026 | 8,026 | 27 May 2026 | By Tomas Kiselak | |||
| Jeffrey W. Albers | SYRE | Stock Option (Right to Buy) | Award | 8,026 | 8,026 | 27 May 2026 | Direct | |||
| Michael Thomas Henderson | SYRE | Stock Option (Right to Buy) | Award | 8,026 | 8,026 | 27 May 2026 | Direct | |||
| Laurie Stelzer | SYRE | Stock Option (Right to Buy) | Award | 8,026 | 8,026 | 27 May 2026 | Direct | |||
| Mark C. McKenna | SYRE | Stock Option (Right to Buy) | Award | 8,026 | 8,026 | 27 May 2026 | Direct | |||
| Sandra Milligan | SYRE | Stock Option (Right to Buy) | Award | 8,026 | 8,026 | 27 May 2026 | Direct | |||
| Michael Thomas Henderson | SYRE | Common Stock | Sale | -47.4% | $5,952,050 | $74.40 | -80,000 | 88,606 | 08 May 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Sale | -11.3% | $892,125 | $71.37 | -12,500 | 97,994 | 01 May 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Options Exercise | 12.8% | 12,500 | 110,494 | 01 May 2026 | Direct | ||
| Scott L. Burrows | SYRE | Stock Option (Right to Buy) | Options Exercise | -3.17% | -12,500 | 382,357 | 01 May 2026 | Direct | ||
| Sheldon Sloan | SYRE | Common Stock | Sale | -100% | $5,600,701 | $71.50 | -78,333 | 0 | 01 May 2026 | Direct |
| Sheldon Sloan | SYRE | Common Stock | Options Exercise | 78,333 | 78,333 | 01 May 2026 | Direct | |||
| Sheldon Sloan | SYRE | Stock Option (Right to Buy) | Options Exercise | -19.6% | -78,333 | 321,667 | 01 May 2026 | Direct | ||
| Cameron Turtle | SYRE | Common Stock | Sale | -2.39% | $1,070,507 | $71.37 | -15,000 | 612,540 | 01 May 2026 | Direct |
| Cameron Turtle | SYRE | Common Stock | Sale | -2.33% | $739,912 | $49.33 | -15,000 | 627,540 | 01 Apr 2026 | Direct |
| Sheldon Sloan | SYRE | Common Stock | Sale | -100% | $397,900 | $50.00 | -7,958 | 0 | 01 Apr 2026 | Direct |
| Sheldon Sloan | SYRE | Common Stock | Options Exercise | 7,958 | 7,958 | 01 Apr 2026 | Direct | |||
| Sheldon Sloan | SYRE | Stock Option (Right to Buy) | Options Exercise | -8.33% | -7,958 | 87,542 | 01 Apr 2026 | Direct |
* marks a reported price that did not pass the local price check.