🕵️ Prothena Corp Public Ltd Co ($PRTA)
SEC insider & ownership activity, last 12 months · CIK 1559053 · every row links its SEC filing
Over the last 12 months insiders bought $3.1M with no open-market selling against it. William P. Scully bought $3.1M (May–Jun). 3 planned sales are pending, the largest $740K (Michael J. Malecek). No red-flag 8-Ks in the window.
Monthly net open-market insider flow, last 12 months (up = net buying)
Insider flow
1 buyer, $3.1M (5 lots) · 0 sellers, $0 (0 lots)
| Insider | Buys | Bought | Sells | Sold | Last |
|---|---|---|---|---|---|
| William P. Scully | 5 | $3.1M | 0 | – | Jun 16, 2026 |
5%+ holders
| Holder | Stake | Class | Schedule | Event | |
|---|---|---|---|---|---|
| William P. Scully | 10.3% | 13G | May 11, 2026 | filing ↗ | |
| Wellington Management Company LLP | 9.5% | 13G | Feb 10, 2025 | filing ↗ | |
| Rubric Capital Management LP | 9.3% | 13G | May 15, 2026 | filing ↗ | |
| David Rosen | 9.3% | 13G | May 15, 2026 | filing ↗ | |
| Todd W. Fennell | 8.4% | 13G | Nov 12, 2025 | filing ↗ | |
| Blackrock, Inc. | 6.9% | 13G | Jul 29, 2026 | filing ↗ |
Planned insider sales (Form 144)
| Seller | Planned | Approx. sale date | |
|---|---|---|---|
| Anne Kingston | $65K | Jul 29, 2026 | filing ↗ |
| Michael John Isaacs | $71K | Jul 29, 2026 | filing ↗ |
| Michael J. Malecek | $740K | Jun 9, 2026 | filing ↗ |
Material events (8-K)
| Item | Event date | |
|---|---|---|
| Shareholder vote (5.07) | May 14, 2026 | filing ↗ |
| Earnings (2.02) | May 7, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | May 7, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | Feb 27, 2026 | filing ↗ |
| Other events (8.01) | Feb 27, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Feb 27, 2026 | filing ↗ |
| Earnings (2.02) | Feb 19, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Feb 19, 2026 | filing ↗ |
| Officer/director changes (5.02) | Dec 10, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Dec 10, 2025 | filing ↗ |
| Shareholder vote (5.07) | Nov 19, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Nov 19, 2025 | filing ↗ |
| Earnings (2.02) | Nov 6, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Nov 6, 2025 | filing ↗ |
| Other events (8.01) | Aug 27, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Aug 27, 2025 | filing ↗ |
| Other events (8.01) | Aug 6, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Aug 6, 2025 | filing ↗ |
| Earnings (2.02) | Aug 4, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Aug 4, 2025 | filing ↗ |
| Officer/director changes (5.02) | Jul 30, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jul 30, 2025 | filing ↗ |