PROTHENA CORP PUBLIC LTD CO (PRTA) has 140 open-market insider trades by 18 insiders since 2014. Over the last six months insiders net bought $10.9M. The most active filer is Karin L. Walker, CAO.
| Name | Title | Tier | Trades | Value | Last Trade |
|---|---|---|---|---|---|
| EcoR1 Capital, LLC | 10% Owner | — | 7 | $250.8M | 2025-05-06 |
| Co Plc Perrigo | 10% | — | 1 | $79.4M | 2014-02-03 |
| Arthur W. Homan | 10% Owner | — | 16 | $8.7M | 2026-10-14 |
| Gene G. Kinney | CEOPres | — | 13 | $8.2M | 2026-07-28 |
| Karin L. Walker | CAO | — | 18 | $8.0M | 2026-07-28 |
| William P. Scully | 10% Owner | — | 8 | $7.6M | 2026-08-20 |
| Lars Ekman | Dir | — | 6 | $7.6M | 2023-01-03 |
| Michael J. Malecek | CLO | — | 5 | $7.2M | 2025-07-28 |
| Tran Nguyen | CFOCSO | — | 11 | $6.2M | 2026-07-28 |
| Wagner M. Zago | CSO | — | 4 | $6.1M | 2026-07-28 |
| Insider | Title | Type | Value | Date |
|---|---|---|---|---|
| Arthur W. Homan | 10% Owner | Buy | $920K | 2026-10-13 |
| Arthur W. Homan | 10% Owner | Buy | $1.8M | 2026-10-07 |
| Arthur W. Homan | 10% Owner | Buy | $857K | 2026-10-02 |
| Arthur W. Homan | 10% Owner | Buy | $1.4M | 2026-09-29 |
| Arthur W. Homan | 10% Owner | Buy | $890K | 2026-09-28 |
| Arthur W. Homan | 10% Owner | Buy | $843K | 2026-09-18 |
Companies that share insiders with PRTA, and sector peers with recent insider buying. Related by who files, not by how the stocks move.
| Arthur W. Homan | 10% Owner | Buy | $256K | 2026-09-02 |
| William P. Scully | 10% Owner | Buy | $439K | 2026-08-20 |
| William P. Scully | 10% Owner | Buy | $323K | 2026-08-07 |
| Michael John Isaacs | CLO & Secretary | Sell | $71K | 2026-07-29 |
| Anne Evans Kingston | CSO | Sell | $65K | 2026-07-29 |
| William P. Scully | 10% Owner | Buy | $158K | 2026-06-16 |
| William P. Scully | 10% Owner | Buy | $1.0M | 2026-06-11 |
| William P. Scully | 10% Owner | Buy | $465K | 2026-06-04 |
| William P. Scully | 10% Owner | Buy | $471K | 2026-06-02 |