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: −$2.02M (9 inflow days, 11 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 45.3% of shares outstanding.
Reported short interest has fallen from 5.09% to 4.18% of float over the last 6 biweekly reports (30 Jun 2026 to 15 Sep 2026).
| Holder | Type | Period | Share change | New stake |
|---|---|---|---|---|
| Nuveen Asset Management LLC | Insurance Company | 2026/Q3 | +755,879 | 0.8% |
| Rubric Capital Management LP | Hedge Fund | 2026/Q3 | +2,100,000 | 9.5% |
| BlackRock | Mutual Fund | 2026/Q3 | +1,589,030 | 5.0% |
| Opaleye Management Inc. | Hedge Fund | 2026/Q3 | +1,426,741 | 3.7% |
| Woodline Partners LP | Hedge Fund | 2026/Q3 | +1,199,812 | 1.6% |
| Jacobs Levy Equity Management Inc | Mutual Fund | 2026/Q3 | +1,001,433 | 1.1% |
| Heights Capital Management, Inc. | VC/PE Fund | 2026/Q3 | +850,000 | 0.9% |
| State Street Global Advisors | Mutual Fund | 2026/Q3 | +639,844 | 1.5% |
| Long Focus Capital Management LLC | Hedge Fund | 2026/Q3 | +555,555 | 1.1% |
| Citadel Advisors LLC | Hedge Fund | 2026/Q3 | +534,494 | 0.7% |
| Teachers Insurance and Annuity Association-College Retirement Equities Fund | Mutual Fund | 2026/Q3 | +505,858 | 0.7% |
| Janus Henderson Group plc | Mutual Fund | 2026/Q3 | +475,757 | 0.5% |
| Perceptive Advisors LLC | VC/PE Fund | 2026/Q3 | +460,555 | 11.2% |
| PFM Health Sciences, LP | Hedge Fund | 2026/Q3 | +455,286 | 0.5% |
| D. E. Shaw & Co., L.P. | Hedge Fund | 2026/Q3 | +427,621 | 0.9% |
Institutional buy/sell activity by reporting period, largest moves first.
| Date | Insider | Title | Transaction | Shares | Price | Held after |
|---|---|---|---|---|---|---|
| 5 Oct 2026 | Stuart Naylor | Chief Development Officer | Intent to Sell (Form 144) | -27,659 | $10.64 | – |
| 22 Sep 2026 | Alan Sebulsky | Director | Other Derivative Acquisition | +100,000 | – | 100,000 |
| 22 Sep 2026 | Apothecary Capital LLC | Initial Statement of Beneficial | +0 | – | 34,500 | |
| 17 Aug 2026 | Alexandria Forbes | Chief Executive Officer | Automatic Disposition | -62,000 | $13.86 | 1,325,695 |
| 20 Jul 2026 | Richard Giroux | Chief Financial Officer | Automatic Disposition | -56,000 | $12.51 | 998,682 |
| 6 Jul 2026 | Stuart Naylor | Chief Development Officer | Automatic Disposition | -27,659 | $14.90 | 640,846 |
| 24 Jun 2026 | Alexandria Forbes | Chief Executive Officer | Other Derivative Acquisition | +980,000 | – | 980,000 |
| 24 Jun 2026 | Richard Giroux | Chief Financial Officer | Other Derivative Acquisition | +980,000 | – | 980,000 |
| 24 Jun 2026 | Stuart Naylor | Chief Development Officer | Other Derivative Acquisition | +70,000 | – | 70,000 |
| 24 Jun 2026 | Robert Zeldin | Chief Medical Officer | Other Derivative Acquisition | +100,000 | – | 100,000 |
| 24 Jun 2026 | Robert Wollin | General Counsel | Other Derivative Acquisition | +100,000 | – | 100,000 |
| 10 Jun 2026 | Jiuyun Yu | Independent Director | Other Derivative Acquisition | +60,000 | – | 60,000 |
| 10 Jun 2026 | Thomas Shenk | Independent Director & Member of Scientific Advisory Board | Other Derivative Acquisition | +69,662 | – | 69,662 |
| 10 Jun 2026 | Keith Harris | Independent Chairperson | Other Derivative Acquisition | +106,441 | – | 106,441 |
| 10 Jun 2026 | Perceptive Advisors LLC | Other Derivative Acquisition | +60,000 | – | 60,000 | |
| 10 Jun 2026 | Nicole Seligman | Independent Director | Other Derivative Acquisition | +60,000 | – | 60,000 |
| 10 Jun 2026 | Neil Mendoza | Independent Director | Other Derivative Acquisition | +66,641 | – | 66,641 |
| 10 Jun 2026 | Ellen Hukkelhoven | Independent Director | Other Derivative Acquisition | +60,000 | – | 60,000 |
| 9 Jun 2026 | Keith Harris | Independent Chairperson | Derivative Exercise and Retained | +75,000 | – | 200,000 |
| 18 May 2026 | Alexandria Forbes | Chief Executive Officer | Automatic Disposition | -62,000 | $9.17 | 1,387,695 |
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 | 4,011,818 | 4.2% | 6.1 |
| 31 Aug 2026 | 3,723,321 | 3.9% | 4.7 |
| 14 Aug 2026 | 3,738,795 | 3.9% | 8.1 |
| 31 Jul 2026 | 3,897,920 | 4.2% | 8.3 |
| 15 Jul 2026 | 4,215,627 | 4.6% | 3.7 |
| 30 Jun 2026 | 4,717,099 | 5.1% | 3.0 |
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