| Filer | Ownership | Change % | Holdings Value | Net Change | Nb Shares | Change % | Reporting Name | Report Period |
|---|---|---|---|---|---|---|---|---|
| SymBiosis Capital Partners, LLC | 6.3% | $2,582,018 | 421,926 | SymBiosis Capital Partners, LLC | 30 Sep 2025 | |||
| RENAISSANCE TECHNOLOGIES LLC | 4.3% | -17% | $1,576,125 | -$310,437 | 287,614 | -16% | Renaissance Technologies LLC | 31 Dec 2025 |
| PRICE T ROWE ASSOCIATES INC /MD/ | 3.1% | -61% | $1,148,833 | -$2,011,971 | 209,641 | -64% | T. Rowe Price Associates, Inc. | 31 Dec 2025 |
As of 31 Dec 2025, 44 institutional investors reported holding 4,306,676 shares of Generation Bio Co. - COMMON STOCK (GBIO). This represents 64% of the company’s total 6,762,613 outstanding shares.
The largest institutional shareholders of Generation Bio Co. - COMMON STOCK (GBIO) together control 61% of the company’s outstanding shares — a level of ownership often associated with strong institutional conviction and long‑term capital commitment.
| Institution | Ownership % | Shares Held | Share Change % | Portfolio % | Holdings Value |
|---|---|---|---|---|---|
| Atlas Venture Life Science Advisors, LLC | 12% | 827,946 | 0.54% | $4,702,732 | |
| SymBiosis Capital Partners, LLC | 9.8% | 665,000 | 0% | 3.9% | $3,777,200 |
| Opaleye Management Inc. | 4.6% | 310,000 | 0.23% | $1,760,800 | |
| RENAISSANCE TECHNOLOGIES LLC | 4.3% | 287,614 | -16% | 0% | $1,633,648 |
| VANGUARD GROUP INC | 3.4% | 229,833 | 0% | 0% | $1,305,451 |
| PRICE T ROWE ASSOCIATES INC /MD/ | 3.1% | 209,641 | -64% | 0% | $1,191,000 |
| Siren, L.L.C. | 3% | 201,419 | -32% | 0.03% | $1,144,060 |
| UBS Group AG | 2.4% | 164,716 | +11% | 0% | $935,587 |
| MORGAN STANLEY | 2.4% | 161,378 | -1.8% | 0% | $916,627 |
| MARSHALL WACE, LLP | 2.1% | 140,294 | -36% | 0% | $796,870 |
| ACADIAN ASSET MANAGEMENT LLC | 1.8% | 121,029 | -5.1% | 0% | $686,000 |
| Yiheng Capital Management, L.P. | 1.6% | 105,524 | 0% | 0.26% | $599,376 |
| Rangeley Capital, LLC | 1.5% | 98,280 | 0.49% | $558,230 | |
| GOLDMAN SACHS GROUP INC | 1.4% | 91,527 | -23% | 0% | $519,873 |
| MILLENNIUM MANAGEMENT LLC | 1.3% | 88,563 | -9% | 0% | $503,038 |
| BANK OF AMERICA CORP /DE/ | 1.3% | 84,842 | +0.03% | 0% | $481,903 |
| BlackRock, Inc. | 0.89% | 60,070 | -0.08% | 0% | $341,197 |
| GEODE CAPITAL MANAGEMENT, LLC | 0.77% | 51,795 | +4% | 0% | $294,268 |
| TWO SIGMA INVESTMENTS, LP | 0.75% | 50,557 | +306% | 0% | $287,164 |
| CITADEL ADVISORS LLC | 0.7% | 47,245 | +0.1% | 0% | $268,352 |
| DRW Securities, LLC | 0.65% | 43,812 | 0.02% | $248,852 | |
| DELTEC ASSET MANAGEMENT LLC | 0.48% | 32,650 | 0.03% | $185,452 | |
| TD Asset Management Inc | 0.39% | 26,708 | 0% | 0% | $151,701 |
| TORNO CAPITAL, LLC | 0.37% | 25,000 | 0.13% | $142,000 | |
| Lynx1 Capital Management LP | 0.37% | 25,000 | 0.03% | $142,000 |