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
FMR LLC
Comparable rows
7/50
Latest evidence
07 Oct 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
-
7 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
-
07 Oct 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
FMR LLC
Comparable rows
7/50
Latest evidence
07 Oct 2026
13D/G
3/4/5
13F
Lead comparable stake: 10%
43 rows are not safely comparable across share classes.
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%.
7 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%
Paradigm Biocapital Advisors LP
5.1%
PERCEPTIVE ADVISORS LLC
4.9%
RTW INVESTMENTS, LP
4.8%
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
Harwin Peter Evan · Director
|
10%
Reported 13D/G
· 07 Oct 2026
|
$906,856,108
10,185,961 shares
|
+$46,185,203 | 07 Oct 2026 |
| BlackRock, Inc. |
13F
13D/G
Company
|
6.6%
Reported 13D/G
· 30 Jun 2025
|
$577,656,391
6,506,605 shares
|
— | 30 Jun 2026 |
| Paradigm Biocapital Advisors LP |
13D/G
13F
Company
|
5.1%
Reported 13D/G
· 24 Sep 2026
|
$403,844,970
4,457,450 shares
|
$0 | 24 Sep 2026 |
| PERCEPTIVE ADVISORS LLC |
13F
13D/G
Company
|
4.9%
Reported 13D/G
· 30 Jun 2026
|
$383,484,855
4,319,496 shares
|
— | 30 Jun 2026 |
| RTW INVESTMENTS, LP |
13F
13D/G
Company
|
4.8%
Reported 13D/G
· 30 Jun 2026
|
$377,492,205
4,251,996 shares
|
— | 30 Jun 2026 |
| Venrock Healthcare Capital Partners III, L.P. |
13D/G
|
4.6%
Reported 13D/G
· 31 Dec 2024
|
$40,335,429
2,685,448 shares
|
$0 | 31 Dec 2024 |
| TANG CAPITAL MANAGEMENT LLC |
13F
13D/G
Company
|
2.4%
Reported 13D/G
· 31 Dec 2025
|
$167,989,516
1,892,200 shares
|
— | 30 Jun 2026 |
| FMR LLC |
13F
Company
|
—
denominator unverified
|
$1,156,464,882
13,026,187 shares
|
— | 30 Jun 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: -$1,641,958,681.
Buys
$0
Insiders: 0
Sells
$1,641,958,681
Insiders: 10
Net
-$1,641,958,681
Shares: -19,343,146
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 0
Shares: 19,343,146
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 183,564 | $0 | $16,903,263 | -$16,903,263 |
| 3-6 | 0 | 19,021,624 | $0 | $1,620,375,732 | -$1,620,375,732 |
| 6-9 | 0 | 62,958 | $0 | $2,734,419 | -$2,734,419 |
| 9-12 | 0 | 75,000 | $0 | $1,945,267 | -$1,945,267 |
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
-$1,641,958,680
Latest report
01 Oct 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Cameron Turtle | Chief Executive Officer, Director | $50,480,381 | -$11,374,650 | -18% | Filing P/S | 01 Oct 2026 |
| Fairmount Healthcare Fund II L.P. | 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 |
| Peter Evan Harwin | Director | $40,961,112 | -$399,658,667 | -91% | Mixed | 23 Jun 2026 |
| Fairmount Funds Management LLC | Director | $40,961,112 | -$399,658,667 | -91% | Mixed | 23 Jun 2026 |
| Scott L. Burrows | Chief Financial Officer | $7,463,330 | -$9,124,220 | -55% | Filing P/S | 30 Sep 2026 |
| Michael Thomas Henderson | Director | $6,860,600 | -$7,952,050 | -54% | Filing P/S | 22 Jun 2026 |
| Jeffrey W. Albers | Director | $979,804 | -$2,404,190 | -71% | Filing P/S | 07 Aug 2026 |
| Anthony G. Quinn | President & CEO, Director | $579,952 | Mixed | 16 Mar 2022 | ||
| Heidy King-Jones | Chief Legal Officer and Corporate Secretary | $265,893 | -$5,114,430 | -95% | Filing P/S | 01 Oct 2026 |
| Marcio Souza | Director | $63,900 | Mixed | 25 Aug 2022 | ||
| Sheldon Sloan | Chief Medical Officer | $0 | -$7,354,472 | -100% | Mixed | 01 Jul 2026 |
| 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| Heidy King-Jones | SYRE | Common Stock | Sale | -91% | $2,633,902 | $91.03 | -28,933 | 2,845 | 01 Oct 2026 | Direct |
| Heidy King-Jones | SYRE | Common Stock | Options Exercise | 1017% | 28,933 | 31,778 | 01 Oct 2026 | Direct | ||
| Heidy King-Jones | SYRE | Stock Option (Right to Buy) | Options Exercise | -5.66% | -28,933 | 482,478 | 01 Oct 2026 | Direct | ||
| Cameron Turtle | SYRE | Common Stock | Sale | -2.71% | $1,380,105 | $92.01 | -15,000 | 537,540 | 01 Oct 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Sale | -8.59% | $688,756 | $91.83 | -7,500 | 79,762 | 01 Oct 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Options Exercise | 9.4% | 7,500 | 87,262 | 01 Oct 2026 | Direct | ||
| Scott L. Burrows | SYRE | Stock Option (Right to Buy) | Options Exercise | -2.34% | -7,500 | 312,357 | 01 Oct 2026 | Direct | ||
| Scott L. Burrows | SYRE | Common Stock | Sale | -18% | $1,573,075 | $89.89 | -17,500 | 79,762 | 30 Sep 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Options Exercise | 21.9% | 17,500 | 97,262 | 30 Sep 2026 | Direct | ||
| Scott L. Burrows | SYRE | Stock Option (Right to Buy) | Options Exercise | -5.19% | -17,500 | 319,857 | 30 Sep 2026 | Direct | ||
| Heidy King-Jones | SYRE | Common Stock | Sale | -12.3% | $36,000 | $90.00 | -400 | 2,845 | 02 Sep 2026 | Direct |
| Heidy King-Jones | SYRE | Common Stock | Options Exercise | 14.1% | 400 | 3,245 | 02 Sep 2026 | Direct | ||
| Heidy King-Jones | SYRE | Stock Option (Right to Buy) | Options Exercise | -0.08% | -400 | 511,411 | 02 Sep 2026 | Direct | ||
| Scott L. Burrows | SYRE | Common Stock | Sale | -18.6% | $1,629,029 | $89.35 | -18,232 | 79,762 | 02 Sep 2026 | Direct |
| Heidy King-Jones | SYRE | Common Stock | Sale | -90.8% | $2,444,529 | $87.31 | -27,999 | 2,845 | 01 Sep 2026 | Direct |
| Heidy King-Jones | SYRE | Common Stock | Options Exercise | 984.2% | 27,999 | 30,844 | 01 Sep 2026 | Direct | ||
| Heidy King-Jones | SYRE | Stock Option (Right to Buy) | Options Exercise | -5.19% | -27,999 | 511,811 | 01 Sep 2026 | Direct | ||
| Scott L. Burrows | SYRE | Common Stock | Sale | -7.11% | $654,792 | $87.31 | -7,500 | 97,994 | 01 Sep 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Options Exercise | 7.65% | 7,500 | 105,494 | 01 Sep 2026 | Direct | ||
| Scott L. Burrows | SYRE | Stock Option (Right to Buy) | Options Exercise | -2.17% | -7,500 | 337,357 | 01 Sep 2026 | Direct | ||
| Cameron Turtle | SYRE | Common Stock | Sale | -2.64% | $1,309,410 | $87.29 | -15,000 | 552,540 | 01 Sep 2026 | Direct |
| Jeffrey W. Albers | SYRE | Common Stock | Sale | -65.8% | $1,881,840 | $104.55 | -18,000 | 9,360 | 07 Aug 2026 | By Sessions LLC |
| Jeffrey W. Albers | SYRE | Common Stock | Sale | -100% | $522,350 | $104.47 | -5,000 | 0 | 07 Aug 2026 | Direct |
| Jeffrey W. Albers | SYRE | Common Stock | Options Exercise | 5,000 | 5,000 | 07 Aug 2026 | Direct | |||
| Jeffrey W. Albers | SYRE | Stock Option (Right to Buy) | Options Exercise | -10% | -5,000 | 45,000 | 07 Aug 2026 | Direct | ||
| Scott L. Burrows | SYRE | Common Stock | Sale | -7.11% | $716,771 | $95.57 | -7,500 | 97,994 | 03 Aug 2026 | Direct |
| Scott L. Burrows | SYRE | Common Stock | Options Exercise | 7.65% | 7,500 | 105,494 | 03 Aug 2026 | Direct | ||
| Scott L. Burrows | SYRE | Stock Option (Right to Buy) | Options Exercise | -2.13% | -7,500 | 344,857 | 03 Aug 2026 | Direct | ||
| Cameron Turtle | SYRE | Common Stock | Sale | -2.57% | $1,432,705 | $95.51 | -15,000 | 567,540 | 03 Aug 2026 | Direct |
| 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 |
* marks a reported price that did not pass the local price check.