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: −$11.30M (3 inflow days, 17 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 36.0% of shares outstanding.
Reported short interest has fallen from 11.21% to 4.87% of float over the last 6 biweekly reports (30 Jun 2026 to 15 Sep 2026).
| Holder | Type | Period | Share change | New stake |
|---|---|---|---|---|
| Samsara BioCapital LLC | VC/PE Fund | 2026/Q3 | +890,590 | 5.6% |
| Nuveen Asset Management LLC | Insurance Company | 2026/Q3 | +158,746 | 0.2% |
| FMR | Mutual Fund | 2026/Q3 | +5,795,331 | 5.2% |
| T. Rowe Price Group, Inc. | Mutual Fund | 2026/Q3 | +1,913,085 | 4.0% |
| Novo Holdings A/S | VC/PE Fund | 2026/Q3 | +1,100,000 | 0.8% |
| BlackRock | Mutual Fund | 2026/Q3 | +1,047,283 | 6.3% |
| Woodline Partners LP | Hedge Fund | 2026/Q3 | +486,052 | 0.4% |
| D. E. Shaw & Co., L.P. | Hedge Fund | 2026/Q3 | +396,105 | 0.7% |
| State Street Global Advisors | Mutual Fund | 2026/Q3 | +385,454 | 1.7% |
| Citigroup Inc. | Public Company | 2026/Q3 | +286,476 | 0.3% |
| Vanguard Capital Management, LLC | Mutual Fund | 2026/Q3 | +268,142 | 3.7% |
| Geode Capital Management, LLC | Mutual Fund | 2026/Q3 | +250,102 | 1.7% |
| Janus Henderson Group plc | Mutual Fund | 2026/Q3 | +230,714 | 1.8% |
| Vanguard Portfolio Management, LLC | Mutual Fund | 2026/Q3 | +208,603 | 0.7% |
| Trium Capital Managers Ltd | Mutual Fund | 2026/Q3 | +198,877 | 0.3% |
Institutional buy/sell activity by reporting period, largest moves first.
| Date | Insider | Title | Transaction | Shares | Price | Held after |
|---|---|---|---|---|---|---|
| 7 Sep 2026 | Samsara BioCapital LLC | Open Market Disposition | -96,131 | $10.55 | 7,235,809 | |
| 7 Sep 2026 | Samsara BioCapital LLC | Open Market Acquisition | +986,721 | $11.17 | 7,235,809 | |
| 2 Aug 2026 | Roy Hardiman | Chief Business & Legal Officer | Open Market Disposition | -2,692 | $26.37 | 195,496 |
| 2 Aug 2026 | John Schroer | Chief Financial Officer | Open Market Disposition | -3,282 | $26.37 | 3,718 |
| 2 Aug 2026 | David Goldstein | Chief Scientific Officer & Head of CMC | Open Market Disposition | -2,596 | $26.37 | 230,201 |
| 2 Aug 2026 | Jorn Drappa | Chief Medical Officer & Head of Research and Development | Open Market Disposition | -2,447 | $26.37 | 39,925 |
| 2 Aug 2026 | Sanam Pangali | Chief Legal Officer | Open Market Disposition | -1,364 | $26.37 | 3,080 |
| 2 Aug 2026 | Mark Bradley | Chief Development Officer | Open Market Disposition | -2,572 | $26.37 | 70,752 |
| 5 Jul 2026 | Sanam Pangali | Chief Legal Officer | Derivative Exercise and Sale | -5,000 | $28.00 | 1,111 |
| 29 Jun 2026 | Srinivas Akkaraju | Independent Director | Other Acquisition | +3,553 | – | 3,553 |
| 29 Jun 2026 | Srinivas Akkaraju | Independent Director | Other Derivative Acquisition | +15,528 | $28.14 | 15,528 |
| 29 Jun 2026 | Sapna Srivastava | Independent Director | Other Acquisition | +3,553 | – | 3,553 |
| 29 Jun 2026 | Sapna Srivastava | Independent Director | Other Derivative Acquisition | +15,528 | $28.14 | 15,528 |
| 29 Jun 2026 | Lynn Tetrault | Independent Director | Other Acquisition | +3,553 | – | 3,553 |
| 29 Jun 2026 | Lynn Tetrault | Independent Director | Other Derivative Acquisition | +15,528 | $28.14 | 15,528 |
| 29 Jun 2026 | C. Machado | Independent Director | Other Acquisition | +3,553 | – | 3,553 |
| 29 Jun 2026 | C. Machado | Independent Director | Other Derivative Acquisition | +15,528 | $28.14 | 15,528 |
| 29 Jun 2026 | Zhengbin Yao | Independent Director | Other Acquisition | +3,553 | – | 3,553 |
| 29 Jun 2026 | Zhengbin Yao | Independent Director | Other Derivative Acquisition | +15,528 | $28.14 | 15,528 |
| 21 May 2026 | Jorn Drappa | Chief Medical Officer & Head of Research and Development | Derivative Exercise and Retained | +26,852 | $8.84 | 33,889 |
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 | 6,299,106 | 4.9% | 1.0 |
| 31 Aug 2026 | 5,645,753 | 4.4% | 7.1 |
| 14 Aug 2026 | 5,853,901 | 4.5% | 6.5 |
| 31 Jul 2026 | 5,766,070 | 4.5% | 6.1 |
| 15 Jul 2026 | 6,764,417 | 5.3% | 3.8 |
| 30 Jun 2026 | 14,294,503 | 11.2% | 7.6 |
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