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: −$1.57M (6 inflow days, 14 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 42.8% of shares outstanding.
Reported short interest has risen from 1.19% to 1.82% of float over the last 3 biweekly reports (14 Aug 2026 to 15 Sep 2026).
| Holder | Type | Period | Share change | New stake |
|---|---|---|---|---|
| Vanguard Capital Management, LLC | Mutual Fund | 2026/Q3 | +90,644 | 0.2% |
| Vanguard Portfolio Management, LLC | Mutual Fund | 2026/Q3 | +2,430 | 0.0% |
| Deep Track Capital, LP | VC/PE Fund | 2026/Q3 | +3,207,138 | 7.0% |
| Frazier Life Sciences Management, LP | VC/PE Fund | 2026/Q3 | +6,968,703 | 15.3% |
| venBio LLC | VC/PE Fund | 2026/Q3 | +4,181,367 | 9.2% |
| Sanofi | Public Company | 2026/Q3 | +1,082,855 | 2.4% |
| Redmile Group, LLC | Hedge Fund | 2026/Q3 | +982,854 | 2.2% |
| Alamar Biosciences, Inc. | Public Company | 2026/Q3 | +3,229,279 | 7.1% |
| Goldman Sachs Asset Management, L.P. | Mutual Fund | 2026/Q3 | +1,967,074 | 4.3% |
| Tao Fu | Individual/Insider | 2026/Q3 | +548,558 | 1.2% |
| The Goldman Sachs Group, Inc. | Public Company | 2026/Q3 | +468,567 | 1.0% |
| Petter Veiby | Individual/Insider | 2026/Q3 | +104,952 | 0.2% |
| Angie You | Individual/Insider | 2026/Q3 | +52,852 | 0.1% |
| Hubert Chen | Individual/Insider | 2026/Q3 | +2,960 | 0.0% |
| Zaneta Odrowaz | Individual/Insider | 2026/Q3 | +11,116 | 0.0% |
Institutional buy/sell activity by reporting period, largest moves first.
| Date | Insider | Title | Transaction | Shares | Price | Held after |
|---|---|---|---|---|---|---|
| 5 Aug 2026 | Sanofi | Private Acquisition | +300,000 | $17.00 | 1,082,855 | |
| 5 Aug 2026 | Sanofi | Derivative Exercise and Retained | +782,855 | – | 1,082,855 | |
| 5 Aug 2026 | Redmile Group, LLC | Private Acquisition | +200,000 | $17.00 | 982,854 | |
| 5 Aug 2026 | Redmile Group, LLC | Derivative Exercise and Retained | +782,854 | – | 782,854 | |
| 5 Aug 2026 | venBio LLC | Private Acquisition | +382,352 | $17.00 | 4,181,367 | |
| 5 Aug 2026 | venBio LLC | Derivative Exercise and Retained | +3,799,015 | – | 4,181,367 | |
| 5 Aug 2026 | Deep Track Capital, LP | Derivative Exercise and Retained | +1,957,138 | – | 1,957,138 | |
| 5 Aug 2026 | Frazier Life Sciences Management, LP | Private Acquisition | +588,235 | $17.00 | 6,154,213 | |
| 5 Aug 2026 | Frazier Life Sciences Management, LP | Derivative Exercise and Retained | +5,490,629 | – | 6,154,213 | |
| 4 Aug 2026 | Goldman Sachs Asset Management, L.P. | Open Market Derivative Acquisiti | +105,807 | – | 105,807 | |
| 3 Aug 2026 | Sanofi | Initial Statement of Beneficial | +0 | – | 782,855 | |
| 3 Aug 2026 | Mitchell Gold | Independent Director | Other Derivative Acquisition | +27,000 | $17.00 | 27,000 |
| 3 Aug 2026 | Mitchell Gold | Independent Director | Initial Statement of Beneficial | +0 | – | 19,913 |
| 3 Aug 2026 | Angie You | Independent Director | Other Derivative Acquisition | +27,000 | $17.00 | 27,000 |
| 3 Aug 2026 | John Smither | Independent Director | Initial Statement of Beneficial | +0 | – | 72,792 |
| 3 Aug 2026 | Hubert Chen | Chief Medical Officer | Other Derivative Acquisition | +140,000 | $17.00 | 140,000 |
| 3 Aug 2026 | Broad Street Principal Investments, L.L.C. | Initial Statement of Beneficial | +0 | – | 855,179 | |
| 3 Aug 2026 | Tao Fu | Chief Executive Officer | Initial Statement of Beneficial | +0 | – | 803,436 |
| 3 Aug 2026 | Alamar Biosciences, Inc. | Initial Statement of Beneficial | +0 | – | 3,229,278 | |
| 3 Aug 2026 | Zaneta Odrowaz | Chief Business Officer, Treasurer & Secretary | Other Derivative Acquisition | +140,000 | $17.00 | 140,000 |
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 | 831,090 | 1.8% | 4.0 |
| 31 Aug 2026 | 648,541 | 1.5% | 3.1 |
| 14 Aug 2026 | 511,865 | 1.2% | 1.0 |
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