PRTA (Prothena Corporation plc Ordinary Shares)

Insider Trading Activity

Every open-market purchase and sale reported by PRTA officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.

Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.

Form 4 Filings
50
most recent
Open-Market Buys
6
code P
Sales
1
code S
Reporting Insiders
19
current holders
PRTA — Recent Form 4 Transactions (latest 2026-08-10)
FiledInsiderRole TypeSharesValue
2026-08-10 WILLIAM P SCULLY 10%+ Owner Buy
2026-07-30 Anne Evans Kingston Chief Strategy Officer MIXED
2026-07-30 Karin L Walker Chief Accounting Officer MIXED
2026-07-30 Tran Nguyen Chief Strategy Officer and CFO MIXED
2026-07-30 Brandon S. Smith Chief Operating Officer MIXED
2026-07-30 Michael John Isaacs General Counsel & Company Sec. MIXED
2026-07-30 Chad J. Swanson Chief Development Officer MIXED
2026-07-30 Wagner M. Zago Chief Scientific Officer MIXED
2026-07-30 Gene G. Kinney President and CEO MIXED
2026-06-18 WILLIAM P SCULLY 10%+ Owner Buy
2026-06-16 WILLIAM P SCULLY 10%+ Owner G
2026-06-12 WILLIAM P SCULLY 10%+ Owner Buy
2026-06-05 WILLIAM P SCULLY 10%+ Owner Buy
2026-06-03 WILLIAM P SCULLY 10%+ Owner Buy
2026-05-26 WILLIAM P SCULLY 10%+ Owner Buy
2026-05-15 Shane Cooke Director A
2026-05-15 Lars Ekman Director A
2026-05-15 Dennis J. Selkoe Director A
2026-05-15 RICHARD T COLLIER Director A
2026-05-15 William H. Jr. Dunn Director A
2026-05-15 DANIEL G WELCH Director A
2026-04-10 Anne Evans Kingston Chief Strategy Officer A
2026-03-05 Tran Nguyen Chief Strategy Officer and CFO A
2026-03-05 Wagner M. Zago Chief Scientific Officer A
2026-03-05 Gene G. Kinney President and CEO A
2026-03-05 Karin L Walker Chief Accounting Officer A
2026-03-05 Chad J. Swanson Chief Development Officer A
2026-03-05 Brandon S. Smith Chief Operating Officer A
2026-03-05 Michael J Malecek Chief Legal Officer A
2025-07-30 Michael J Malecek Chief Legal Officer A
2025-07-30 Karin L Walker Chief Accounting Officer A
2025-07-30 Brandon S. Smith Chief Operating Officer A
2025-07-30 Wagner M. Zago Chief Scientific Officer A
2025-07-30 Tran Nguyen Chief Strategy Officer and CFO A
2025-07-30 Gene G. Kinney President and CEO A
2025-07-30 Chad J. Swanson Chief Development Officer A
2025-05-16 Shane Cooke Director A
2025-05-16 Dennis J. Selkoe Director A
2025-05-16 Helen Susan Kim Director A
2025-05-16 William H. Jr. Dunn Director A
2025-05-16 Paula K Cobb Director A
2025-05-16 Lars Ekman Director A
2025-05-16 RICHARD T COLLIER Director A
2025-05-16 DANIEL G WELCH Director A
2025-05-06 EcoR1 Capital, LLC 10%+ Owner Sell
2025-05-02 WILLIAM P SCULLY 10%+ Owner MIXED
2025-03-07 David A Ford Chief People Officer A
2025-03-07 Brandon S. Smith Chief Operating Officer A
2025-03-07 Wagner M. Zago Chief Scientific Officer A
2025-03-07 Gene G. Kinney President and CEO A
PRTA — Current Insider Holders
InsiderRole Shares HeldValue
10%+ Owner 8,266,342
10%+ Owner 842,000
Chief Strategy Officer and CFO 97,205
Chief Scientific Officer 85,000
Chief Legal Officer 80,000
President and CEO 68,793
Chief Strategy Officer 55,782
Chief Operating Officer 52,000
President and CEO 42,910
Chief Development Officer 40,733
General Counsel & Company Sec. 35,745
Chief Medical Officer 30,000
Chief Accounting Officer 25,000
Director 9,208
Director 6,219
Director 3,148
Chief Business Officer 2,000
Chief Legal Officer 2,000
Controller 335
How to read Form 4 activity

Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.

Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.

Full filing history and per-insider positions are on the PRTA quote page; the site-wide leaderboard is on the insider transactions hub.