SEC Form 4 · Updated Daily
PRTA
— PROTHENA CORPORATION PUBLIC LIMITED COMPANY OwnershipInsider and institutional ownership derived from SEC Form 4 filings. Click any owner to see their holdings across every company they’ve filed on, and how their position has changed over time.
Current Reporting Owners
| Owner | Role | Shares Owned | As Of | Last Activity |
|---|---|---|---|---|
| NODELMAN OLEG | 10%+ Owner · Director | 9,426,640 | 2019-12-03 | — |
| EcoR1 Capital, LLC | 10%+ Owner | 8,266,342 | 2025-05-02 | S |
| SCULLY WILLIAM P | 10%+ Owner | 1,187,000 | 2026-10-23 | P |
| Kinney Gene G. | Director · Officer | 152,793 | 2026-07-28 | M |
| Smith Brandon S. | Officer | 130,000 | 2026-07-28 | M |
| Nguyen Tran | Officer | 97,205 | 2026-07-28 | M |
| Zago Wagner M. | Officer | 85,000 | 2026-07-28 | M |
| Swanson Chad J. | Officer | 85,000 | 2026-07-28 | M |
| Malecek Michael J | Officer | 80,000 | 2025-07-28 | A |
| Kingston Anne Evans | Officer | 63,444 | 2026-07-28 | F |
| Isaacs Michael John | Officer | 44,131 | 2026-07-28 | F |
| Schenk Dale B. | Director · Officer | 33,333 | 2015-11-17 | M |
| Koller Martin | Officer | 30,000 | 2015-11-13 | M |
| Walker Karin L | Officer | 25,000 | 2026-07-28 | M |
| Ekman Lars | Director | 16,077 | 2023-01-03 | M |
| Nickerson Tara | Officer | 14,776 | 2017-09-28 | M |
| HENNEY CHRISTOPHER S | Director | 11,108 | 2021-07-14 | M |
| Selkoe Dennis J. | Director | 7,845 | 2023-07-03 | M |
| COLLIER RICHARD T | Director | 6,219 | 2023-01-05 | M |
| Cooke Shane | Director | 5,000 | 2023-01-10 | M |
| Karp Carol D. | Officer | 5,000 | 2023-10-04 | M |
| HOMAN ARTHUR W | Officer | 3,125 | 2017-03-01 | M |
| Garren Hideki | Officer | 2,000 | 2023-09-13 | M |
| Fawcett John Randall | Officer | 336 | 2012-12-20 | — |
| PERRIGO Co plc | 10%+ Owner | 0 | 2014-02-03 | S |
| Elan Science One Ltd | 10%+ Owner | 0 | 2014-02-03 | S |
| ELAN CORP PLC | 10%+ Owner | 0 | 2014-02-03 | S |
Recent Filings
| Date | Owner | Activity | Shares | Price | Owned After |
|---|---|---|---|---|---|
| 2026-10-23 | SCULLY WILLIAM P | Open-market buy | 50,000 | $8.07 | 1,187,000 |
| 2026-10-22 | SCULLY WILLIAM P | Open-market buy | 100,000 | $8.19 | 1,137,000 |
| 2026-10-14 | SCULLY WILLIAM P | Open-market buy | 10,000 | $8.46 | 1,037,000 |
| 2026-10-13 | SCULLY WILLIAM P | Open-market buy | 100,000 | $8.35 | 1,027,000 |
| 2026-10-08 | SCULLY WILLIAM P | Open-market buy | 90,000 | $8.57 | 529,000 |
| 2026-10-07 | SCULLY WILLIAM P | Open-market buy | 125,000 | $8.40 | 439,000 |
| 2026-10-02 | SCULLY WILLIAM P | Open-market buy | 100,000 | $8.57 | 314,000 |
| 2026-09-29 | SCULLY WILLIAM P | Open-market buy | 162,000 | $8.68 | 214,000 |
| 2026-09-28 | SCULLY WILLIAM P | Open-market buy | 103,500 | $8.60 | 187,000 |
| 2026-09-18 | SCULLY WILLIAM P | Open-market buy | 100,000 | $8.43 | 927,000 |
| 2026-09-02 | SCULLY WILLIAM P | Open-market buy | 27,000 | $9.47 | 827,000 |
| 2026-08-20 | SCULLY WILLIAM P | Open-market buy | 50,000 | $8.79 | 800,000 |
| 2026-08-18 | SCULLY WILLIAM P | Gift | 627,553 | $0.00 | 750,000 |
| 2026-08-17 | SCULLY WILLIAM P | Gift | 336,000 | $0.00 | 1,377,553 |
| 2026-08-10 | SCULLY WILLIAM P | Gift | 251,553 | $0.00 | 1,041,553 |
| 2026-08-07 | SCULLY WILLIAM P | Open-market buy | 3,500 | $8.62 | 83,500 |
| 2026-08-07 | SCULLY WILLIAM P | Open-market buy | 34,000 | $8.62 | 790,000 |
| 2026-07-29 | Isaacs Michael John | Open-market sale | 8,386 | $8.47 | 35,745 |
| 2026-07-29 | Kingston Anne Evans | Open-market sale | 7,662 | $8.47 | 55,782 |
| 2026-07-28 | Isaacs Michael John | Tax withholding | 4,694 | $8.56 | 44,131 |
| 2026-07-28 | Kingston Anne Evans | Tax withholding | 3,498 | $8.56 | 63,444 |
| 2026-07-28 | Kinney Gene G. | Option exercise (derivative) | 84,000 | $0.00 | 0 |
| 2026-07-28 | Kinney Gene G. | Disposition to issuer | 84,000 | $8.56 | 68,793 |
| 2026-07-28 | Kinney Gene G. | Option exercise | 84,000 | — | 152,793 |
| 2026-07-28 | Nguyen Tran | Option exercise (derivative) | 57,000 | $0.00 | 0 |
| 2026-07-28 | Nguyen Tran | Disposition to issuer | 57,000 | $8.56 | 40,205 |
| 2026-07-28 | Nguyen Tran | Option exercise | 57,000 | — | 97,205 |
| 2026-07-28 | Smith Brandon S. | Option exercise (derivative) | 78,000 | $0.00 | 0 |
| 2026-07-28 | Smith Brandon S. | Disposition to issuer | 78,000 | $8.56 | 52,000 |
| 2026-07-28 | Smith Brandon S. | Option exercise | 78,000 | — | 130,000 |
| 2026-07-28 | Swanson Chad J. | Option exercise (derivative) | 51,000 | $0.00 | 0 |
| 2026-07-28 | Swanson Chad J. | Tax withholding | 3,467 | $8.56 | 40,733 |
| 2026-07-28 | Swanson Chad J. | Disposition to issuer | 40,800 | $8.56 | 44,200 |
| 2026-07-28 | Swanson Chad J. | Option exercise | 51,000 | — | 85,000 |
| 2026-07-28 | Walker Karin L | Option exercise (derivative) | 15,000 | $0.00 | 0 |
| 2026-07-28 | Walker Karin L | Disposition to issuer | 15,000 | $8.56 | 10,000 |
| 2026-07-28 | Walker Karin L | Option exercise | 15,000 | — | 25,000 |
| 2026-07-28 | Zago Wagner M. | Option exercise (derivative) | 51,000 | $0.00 | 0 |
| 2026-07-28 | Zago Wagner M. | Disposition to issuer | 51,000 | $8.56 | 34,000 |
| 2026-07-28 | Zago Wagner M. | Option exercise | 51,000 | — | 85,000 |
Source: SEC EDGAR Form 4 filings. For informational purposes only — not investment advice.