Generation BioGBIO
13F holders, Q2 2025 (June 30)59holders −22
13new positions
35sold out
4famous investors
$0.32avg. 13F price*
At the end of Q2 2025, 59 institutions reported holding Generation Bio Co. (GBIO) in their 13F filings, down 22 from Q1 2025. 13 opened new positions and 35 sold out. The largest holders were T. Rowe Price Associates Inc. ($2.7M), Atlas Venture Life Science Advisors, LLC ($2.7M) and Siren, L.L.C. ($950K). 4 famous investors held it, including Jim Simons / Peter Brown (0.0% of Renaissance Technologies's portfolio), Israel Englander (0.0% of Millennium Management's portfolio) and Ken Griffin (0.0% of Citadel Advisors's portfolio).
- Company
- Generation Bio Co.
- CUSIP
- 37148K100
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q1 2025 → Q2 2025
| Institutions | Total Value | |
|---|---|---|
| New Positions | 13 | $658K |
| Exits | 35 | $852K |
All 13F filers, Q1 2025 → Q2 2025: 3,977,609 shares bought and 10,337,044 shares sold, net −6,359,435 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 59 holders
| T. Rowe Price Associates Inc. | 0.00% | Reduce -6.6% | 8,462,611 | $2.7M |
| Atlas Venture Life Science Advisors, LLC | 0.40% | No change | 8,279,484 | $2.7M |
| Siren, L.L.C. | 0.05% | No change | 2,968,925 | $950K |
| Renaissance Technologies | 0.00% | Add +37.2% | 2,580,780 | $826K |
| FMR LLC | 0.00% | Reduce -50.6% | 2,345,624 | $751K |
| Vanguard Group Inc. | 0.00% | Reduce -12.3% | 2,298,347 | $735K |
| Baker Bros. Advisors LP | 0.01% | No change | 1,944,945 | $623K |
| Acadian Asset Management LLC | 0.00% | Add +6.4% | 1,233,471 | $393K |
| BlackRock, Inc. | 0.00% | Reduce -65.9% | 1,161,578 | $372K |
| Goldman Sachs Group Inc. | 0.00% | Reduce -2.0% | 1,064,090 | $341K |
| Millennium Management | 0.00% | New | 1,061,606 | $340K |
| Yiheng Capital Management, L.P. | 0.12% | Add +451.0% | 1,055,269 | $338K |
| Morgan Stanley | 0.00% | Add +3.9% | 912,834 | $292K |
| UBS Group AG | 0.00% | Reduce -9.5% | 884,902 | $283K |
| Bank of America Corp. | 0.00% | Reduce -32.3% | 871,951 | $279K |
| Militia Capital Partners, LP | 0.08% | New | 542,347 | $174K |
| Squarepoint Ops LLC | 0.00% | Add +18.0% | 518,270 | $166K |
| Geode Capital Management, LLC | 0.00% | Reduce -55.1% | 498,080 | $159K |
| TD Asset Management Inc | 0.00% | No change | 340,686 | $109K |
| Susquehanna International Group, LLP | 0.00% | Add +170.2% | 249,277 | $80K |
| Charles Schwab Investment Management Inc. | 0.00% | Reduce -33.5% | 236,856 | $76K |
| State Street Corp. | 0.00% | Reduce -79.5% | 206,116 | $66K |
| Citadel Advisors | 0.00% | Add +58.4% | 192,160 | $62K |
| Two Sigma Advisers, LP | 0.00% | Reduce -1.3% | 191,400 | $61K |
| Palo Alto Investors LP | 0.01% | No change | 150,475 | $48K |
| Y-Intercept (Hong Kong) Ltd | 0.00% | New | 148,186 | $47K |
| Manufacturers Life Insurance Company, The | 0.00% | No change | 143,980 | $46K |
| Northern Trust Corp. | 0.00% | Reduce -64.0% | 133,090 | $43K |
| Aegis Wealth Management LLC | 0.02% | No change | 88,890 | $36K |
| Two Sigma Investments, LP | 0.00% | Add +0.4% | 105,961 | $34K |
| Callan Family Office, LLC | 0.00% | New | 69,735 | $22K |
| AQR Capital Management | 0.00% | Reduce -28.4% | 63,689 | $20K |
| Accent Capital Management, LLC | 0.01% | New | 38 | $20K |
| Kestra Private Wealth Services, LLC | 0.00% | Add +9.6% | 57,000 | $18K |
| Qube Research & Technologies Ltd | 0.00% | New | 55,588 | $18K |
| Point72 Asia (Singapore) Pte. Ltd. | 0.00% | New | 34,970 | $11K |
| Two Sigma Securities, LLC | 0.00% | New | 32,669 | $10K |
| Abel Hall, LLC | 0.00% | New | 23,565 | $8K |
| Prudential Financial Inc. | 0.00% | Reduce -37.9% | 22,100 | $7K |
| Tower Research Capital LLC (TRC) | 0.00% | Reduce -23.7% | 15,951 | $5K |
| Osaic Holdings, Inc. | 0.00% | No change | 15,459 | $5K |
| PFG Advisors | 0.00% | No change | 15,000 | $5K |
| Mariner, LLC | 0.00% | New | 12,292 | $4K |
| Barclays PLC | 0.00% | Reduce -81.2% | 11,483 | $4K |
| Citigroup Inc. | 0.00% | Reduce -70.2% | 10,359 | $3K |
| Jump Financial, LLC | 0.00% | New | 10,280 | $3K |
| Cwm, LLC | 0.00% | Reduce -20.4% | 6,646 | $2K |
| JPMorgan Chase & Co. | 0.00% | Reduce -97.9% | 4,331 | $1K |
| Royal Bank of Canada | 0.00% | Reduce -42.5% | 3,015 | $1K |
| Russell Investments Group, Ltd. | 0.00% | No change | 2,703 | $865 |
| Sterling Capital Management LLC | 0.00% | Reduce -30.5% | 1,949 | $624 |
| BNP Paribas Financial Markets | 0.00% | Reduce -88.6% | 1,705 | $546 |
| Wells Fargo & Company | 0.00% | Reduce -94.9% | 1,532 | $490 |
| Point72 (DIFC) Ltd | 0.00% | New | 1,446 | $463 |
| Nisa Investment Advisors, LLC | 0.00% | Reduce -27.1% | 1,223 | $391 |
| Raymond James Financial Inc. | 0.00% | New | 600 | $192 |
| PNC Financial Services Group, Inc. | 0.00% | Reduce -85.8% | 255 | $82 |
| First Horizon Advisors, Inc. | 0.00% | No change | 2 | $1 |
| Huntington National Bank | 0.00% | No change | 1 | $0 |
"% of holder's portfolio" is GBIO's weight in each manager's 13F, not the share of Generation Bio Co. the manager owns.