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: −$1.87M (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 28.2% of shares outstanding.
Reported short interest has fallen from 3.67% to 3.62% of float over the last 6 biweekly reports (30 Jun 2026 to 15 Sep 2026).
| Holder | Type | Period | Share change | New stake |
|---|---|---|---|---|
| FMR | Mutual Fund | 2026/Q3 | +586,001 | 1.0% |
| Soleus Capital Management, L.P. | Hedge Fund | 2026/Q3 | +630,000 | 1.0% |
| Balyasny Asset Management L.P. | Hedge Fund | 2026/Q3 | +610,980 | 1.0% |
| Columbia Management Investment Advisers, LLC | Mutual Fund | 2026/Q3 | +370,052 | 0.6% |
| Morgan Stanley | Public Company | 2026/Q3 | +337,686 | 0.7% |
| Crestline Investors Inc. | Hedge Fund | 2026/Q3 | +326,648 | 0.5% |
| Schonfeld Strategic Advisors LLC | Hedge Fund | 2026/Q3 | +269,348 | 0.4% |
| Jane Street Group, LLC | Private Company | 2026/Q3 | +268,224 | 0.6% |
| Propel Bio Management, LLC | Mutual Fund | 2026/Q3 | +191,733 | 0.3% |
| Fred Alger Management, LLC | Mutual Fund | 2026/Q3 | +177,000 | 0.3% |
| ADAR1 Capital Management, LLC | Hedge Fund | 2026/Q3 | +166,216 | 0.6% |
| Caption Management, LLC | Hedge Fund | 2026/Q3 | +162,476 | 0.3% |
| Tetragon Partners UK LLP | Hedge Fund | 2026/Q3 | +134,095 | 1.3% |
| Quadrature Capital Limited | Hedge Fund | 2026/Q3 | +118,129 | 0.2% |
| Two Sigma Investments, LP | Hedge Fund | 2026/Q3 | +104,801 | 0.2% |
Institutional buy/sell activity by reporting period, largest moves first.
| Date | Insider | Title | Transaction | Shares | Price | Held after |
|---|---|---|---|---|---|---|
| 5 Jul 2026 | Richard Griffiths | Private Disposition | -1,544,374 | – | 10,281,486 | |
| 1 Jan 2026 | Timothy McInerney | Director | Other Derivative Acquisition | +90,000 | $2.05 | 90,000 |
| 1 Jan 2026 | David Lemus | Independent Non-Executive Director | Other Derivative Acquisition | +90,000 | $2.05 | 90,000 |
| 1 Jan 2026 | James Ede-Golightly | Independent Non-Executive Director | Other Derivative Acquisition | +90,000 | $2.05 | 90,000 |
| 1 Jan 2026 | Steven Romano | Chief Medical Officer and Head of Research & Development | Other Derivative Acquisition | +300,000 | $2.05 | 300,000 |
| 1 Jan 2026 | Rhonda Hellums | Chief Financial Officer | Other Derivative Acquisition | +375,000 | $2.05 | 375,000 |
| 21 Dec 2025 | James Ede-Golightly | Independent Non-Executive Director | Other Derivative Acquisition | +90,000 | $2.15 | 90,000 |
| 17 Dec 2025 | Ian Ross | Other Derivative Acquisition | +900,000 | $2.08 | 900,000 | |
| 13 Dec 2025 | James Ede-Golightly | Independent Non-Executive Director | Initial Statement of Beneficial | +0 | – | 105,333 |
| 26 Oct 2025 | Richard Griffiths | Other Derivative Acquisition | +2,000 | $7.75 | 11,819,861 | |
| 26 Oct 2025 | Richard Griffiths | Open Market Derivative Acquisiti | +22,000 | $7.75 | 11,825,861 | |
| 2 Aug 2025 | Richard Griffiths | Open Market Derivative Dispositi | -20,000 | $5.45 | 11,805,861 | |
| 31 Jul 2025 | Richard Griffiths | Private Acquisition | +18,376 | – | 11,220,687 | |
| 29 Jul 2025 | Richard Griffiths | Private Acquisition | +23,482 | – | 11,202,311 | |
| 10 Jul 2025 | Richard Griffiths | Private Acquisition | +71,293 | – | 11,153,484 | |
| 8 Jul 2025 | Richard Griffiths | Private Acquisition | +62,457 | – | 11,082,191 | |
| 26 Jun 2025 | Richard Griffiths | Private Acquisition | +110,474 | – | 11,019,734 | |
| 23 Jun 2025 | Richard Griffiths | Private Acquisition | +82,606 | – | 10,909,260 | |
| 17 Jun 2025 | Richard Griffiths | Open Market Acquisition | +70,448 | $5.29 | 10,826,654 | |
| 11 Jun 2025 | Richard Griffiths | Private Acquisition | +39,305 | – | 10,756,206 |
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 | 2,178,055 | 3.6% | 2.5 |
| 31 Aug 2026 | 2,435,831 | 4.0% | 3.5 |
| 14 Aug 2026 | 2,432,830 | 4.0% | 1.0 |
| 31 Jul 2026 | 1,837,238 | 3.9% | 3.3 |
| 15 Jul 2026 | 1,572,687 | 3.3% | 3.2 |
| 30 Jun 2026 | 1,733,018 | 3.7% | 2.2 |
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