Who holds it, who is betting against it, and where the big money is moving
Net of large-order buying minus selling, in USD. Over this window: +$4.76M (10 inflow days, 10 outflow days).
Super/Big orders approximate institutional-size trades; Mid/Small approximate retail-size trades. Net buy minus sell value in each bucket, summed over the window.
The five largest holders on file together own 41.5% of shares outstanding.
Reported short interest has risen from 6.21% to 6.78% of float over the last 6 biweekly reports (30 Jun 2026 to 15 Sep 2026).
| Holder | Type | Period | Share change | New stake |
|---|---|---|---|---|
| T. Rowe Price Group, Inc. | Mutual Fund | 2026/Q3 | +4,425,270 | 16.0% |
| Frazier Life Sciences Management, LP | VC/PE Fund | 2026/Q3 | +3,750,000 | 3.7% |
| Deep Track Capital, LP | VC/PE Fund | 2026/Q3 | +3,706,734 | 3.7% |
| Adage Capital Management, L.P. | Hedge Fund | 2026/Q3 | +3,477,222 | 8.1% |
| BlackRock | Mutual Fund | 2026/Q3 | +3,425,004 | 3.9% |
| Wellington Management Group | Mutual Fund | 2026/Q3 | +1,767,938 | 1.8% |
| Vanguard Capital Management, LLC | Mutual Fund | 2026/Q3 | +1,069,516 | 3.7% |
| Boxer Capital Management, LLC | Hedge Fund | 2026/Q3 | +1,000,000 | 1.0% |
| Prosight Management, LP | Hedge Fund | 2026/Q3 | +953,438 | 5.9% |
| Vanguard Portfolio Management, LLC | Mutual Fund | 2026/Q3 | +946,985 | 0.9% |
| Geode Capital Management, LLC | Mutual Fund | 2026/Q3 | +939,051 | 1.6% |
| State Street Global Advisors | Mutual Fund | 2026/Q3 | +762,626 | 1.0% |
| Nextbio Capital Management LP | Hedge Fund | 2026/Q3 | +577,441 | 3.7% |
| Pinnacle Associates, Ltd. | Mutual Fund | 2026/Q3 | +503,219 | 1.9% |
| Northern Trust Global Investments | Mutual Fund | 2026/Q3 | +394,255 | 0.5% |
Institutional buy/sell activity by reporting period, largest moves first.
| Date | Insider | Title | Transaction | Shares | Price | Held after |
|---|---|---|---|---|---|---|
| 5 Jul 2026 | Abhinav Shukla | Chief Technology Officer | Derivative Exercise and Retained | +12,153 | $3.57 | 75,295 |
| 1 Jul 2026 | Abhinav Shukla | Chief Technology Officer | Derivative Exercise and Sale | -410 | $7.01 | 75,295 |
| 30 Jun 2026 | Abhinav Shukla | Chief Technology Officer | Intent to Sell (Form 144) | -100 | $7.07 | – |
| 30 Jun 2026 | Abhinav Shukla | Chief Technology Officer | Derivative Exercise and Sale | -23,465 | $7.08 | 63,143 |
| 29 Jun 2026 | Arunthathy Pandite | Chief Medical Officer | Automatic Disposition | -30,000 | $7.01 | 136,219 |
| 29 Jun 2026 | Abhinav Shukla | Chief Technology Officer | Intent to Sell (Form 144) | -23,365 | $7.08 | – |
| 10 Jun 2026 | OrbiMed Advisors LLC | Open Market Derivative Acquisiti | +1,250,000 | $0.00 | 5,303,908 | |
| 8 Jun 2026 | Clay Siegall | Director | Open Market Acquisition | +62,500 | $4.00 | 318,608 |
| 7 Jun 2026 | OrbiMed Advisors LLC | Other Derivative Acquisition | +18,439,788 | $0.00 | 5,095,575 | |
| 7 Jun 2026 | Mona Ashiya | Director | Other Derivative Acquisition | +18,439,788 | $0.00 | 5,095,575 |
| 28 May 2026 | Clay Siegall | Director | Other Derivative Acquisition | +81,000 | $5.95 | 81,000 |
| 28 May 2026 | Neil W. Gibson | Independent Director | Other Derivative Acquisition | +81,000 | $5.95 | 81,000 |
| 28 May 2026 | Mona Ashiya | Director | Other Derivative Acquisition | +81,000 | $5.95 | 81,000 |
| 28 May 2026 | George Golumbeski | Independent Chairperson | Other Derivative Acquisition | +81,000 | $5.95 | 81,000 |
| 28 May 2026 | Helen Boudreau | Independent Director | Other Derivative Acquisition | +81,000 | $5.95 | 81,000 |
| 28 May 2026 | Daniel Baker | Director | Other Derivative Acquisition | +81,000 | $5.95 | 81,000 |
| 21 May 2026 | Clay Siegall | Director | Derivative Exercise and Retained | +128,054 | $1.08 | 256,108 |
| 20 May 2026 | Abhinav Shukla | Chief Technology Officer | Derivative Exercise and Retained | +5,122 | $1.08 | 63,143 |
| 14 May 2026 | Stephen Stout | General Counsel, Corporate Secretary and Chief Ethics & Compliance Officer | Other Acquisition | +12,805 | $1.08 | 62,866 |
| 11 May 2026 | Taylor Schreiber | Chief Executive Officer | Derivative Exercise and Retained | +25,610 | $1.08 | 2,732,972 |
From Form 4/Form 144 filings. Negative share counts are disposals (sales, gifts, or shares withheld for taxes); positive are acquisitions.
| Report date | Shares short | % of float | Days to cover |
|---|---|---|---|
| 15 Sep 2026 | 6,808,662 | 6.8% | 8.4 |
| 31 Aug 2026 | 5,571,195 | 5.6% | 7.6 |
| 14 Aug 2026 | 6,006,320 | 6.0% | 5.8 |
| 31 Jul 2026 | 6,394,445 | 6.7% | 5.3 |
| 15 Jul 2026 | 7,802,903 | 8.2% | 5.8 |
| 30 Jun 2026 | 5,929,245 | 6.2% | 2.6 |
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