| Rank | Holder | SharesFloat % | Change | Date reported |
|---|---|---|---|---|
| 1 | FMR Inc | 8.93M (16.39%) | 3.05M Increased by +34.15% | Dec 31, 25 |
| 2 | Baker Bros Advisors LP | 8.66M (15.89%) | 2.01M Increased by +23.17% | Dec 31, 25 |
| 3 | venBio Select Advisor LLC | 7.47M (13.72%) | 1.12M Increased by +15.05% | Dec 31, 25 |
| 4 | Vanguard Group Inc | 6.27M (11.50%) | 845.92K Increased by +13.50% | Dec 31, 25 |
| 5 | Bvf Inc | 5.50M (10.10%) | 0.00 Increased by 0.00% | Dec 31, 25 |
| 6 | T. Rowe Price Associates, Inc. | 5.10M (9.36%) | -1.76M Decreased by -34.56% | Sep 30, 25 |
| 7 | Atlas Venture Life Science Advisors, LLC | 4.66M (8.55%) | -236.59K Decreased by -5.08% | Dec 31, 25 |
| 8 | Wellington Management Company LLP | 4.41M (8.10%) | -782.76K Decreased by -17.74% | Dec 31, 25 |
| 9 | BlackRock Inc | 4.37M (8.01%) | 217.19K Increased by +4.98% | Sep 30, 25 |
| 10 | Siren, L.L.C. | 3.29M (6.03%) | -141.32K Decreased by -4.30% | Dec 31, 25 |
| 11 | Artal Group S A | 3.01M (5.52%) | -21.52K Decreased by -0.72% | Jun 30, 24 |
| 12 | State Street Corporation | 2.67M (4.91%) | 778.24K Increased by +29.12% | Mar 31, 24 |
| 13 | State Street Corp | 2.02M (3.71%) | 465.02K Increased by +23.03% | Sep 30, 25 |
| 14 | Capital Research Global Investors | 1.56M (2.86%) | 298.61K Increased by +19.13% | Dec 31, 25 |
| 15 | Geode Capital Management, LLC | 1.42M (2.60%) | 140.62K Increased by +9.92% | Dec 31, 25 |
| 16 | Driehaus Capital Management LLC | 1.07M (1.96%) | 130.14K Increased by +12.17% | Dec 31, 25 |
| 17 | Aquilo Capital Management, LLC | 881.34K (1.62%) | 99.12K Increased by +11.25% | Dec 31, 23 |
| 18 | UBS Asset Mgmt Americas Inc | 863.76K (1.59%) | 44.84K Increased by +5.19% | Sep 30, 25 |
| 19 | Jennison Associates LLC | 825.02K (1.51%) | 272.74K Increased by +33.06% | Jun 30, 25 |
| 20 | Redmile Group, LLC | 803.29K (1.47%) | -180.12K Decreased by -22.42% | Jun 30, 25 |
| Rank | Holder | SharesFloat % | Change | Date reported |
|---|---|---|---|---|
| 1 | Fidelity Growth Compy Commingled Pl S | 2.85M (5.24%) | 27.37K Increased by +0.96% | Jan 31, 26 |
| 2 | Fidelity Growth Compy Commingled Pl O | 2.24M (4.10%) | 52.60K Increased by +2.35% | Aug 31, 24 |
| 3 | Vanguard Health Care Inv | 2.17M (3.99%) | -215.16K Decreased by -9.91% | Dec 31, 25 |
| 4 | Vanguard Total Stock Mkt Idx Inv | 2.13M (3.90%) | 4.47K Increased by +0.21% | Feb 28, 26 |
| 5 | Fidelity Growth Company Fund | 2.04M (3.75%) | 14.00K Increased by +0.69% | Jan 31, 26 |
| 6 | US Small-Cap Growth II Equity Comp | 1.97M (3.61%) | 116.38K Increased by +5.92% | Dec 31, 25 |
| 7 | T. Rowe Price New Horizons | 1.96M (3.60%) | -2.01K Decreased by -0.10% | Jan 31, 26 |
| 8 | Vanguard US Total Market Shares ETF | 1.54M (2.83%) | 1.91K Increased by +0.12% | Sep 30, 24 |
| 9 | Vanguard Small Cap Index | 1.52M (2.80%) | 4.15K Increased by +0.27% | Feb 28, 26 |
| 10 | American Funds SMALLCAP World A | 1.39M (2.55%) | 276.47K Increased by +19.91% | Dec 31, 25 |
| 11 | iShares Russell 2000 ETF | 1.37M (2.52%) | 565.76K Increased by +41.27% | Feb 28, 26 |
| 12 | T. Rowe Price Health Sciences | 1.10M (2.03%) | -129.68K Decreased by -11.74% | Jan 31, 26 |
| 13 | State Street® SPDR® S&P® Biotech ETF | 982.40K (1.80%) | 5.42K Increased by +0.55% | Feb 28, 26 |
| 14 | T. Rowe Price New Horizons Tr-Z | 872.24K (1.60%) | 65.62K Increased by +7.52% | Mar 31, 25 |
| 15 | Vanguard Small Cap Growth Index Inv | 846.44K (1.55%) | 1.35K Increased by +0.16% | Feb 28, 26 |
| 16 | T. Rowe Price New Horizons Tr-A | 845.51K (1.55%) | 201.41K Increased by +23.82% | Dec 31, 25 |
| 17 | Vanguard Institutional Extnd Mkt Idx Tr | 662.71K (1.22%) | 5.69K Increased by +0.86% | Feb 28, 26 |
| 18 | Vanguard Explorer Inv | 644.63K (1.18%) | -333.27K Decreased by -51.70% | Dec 31, 25 |
| 19 | Eventide Healthcare & Life Sciences I | 626.00K (1.15%) | -18.56K Decreased by -2.96% | Dec 31, 25 |
| 20 | Fidelity Contrafund | 607.50K (1.12%) | 607.50K Increased by +100.00% | Dec 31, 25 |