William P Scully bought $2.7M of Prothena (PRTA)
Executed Dec 18 2024, disclosed May 2 2025, 135 days later, against a two-business-day limit.
Over the 21 trading sessions from the disclosed entry session (May 2 2025), the stock returned -46.7% (delay-adjusted); from the execution session (Dec 18 2024), +0.6%. Derived: entry at the session's open, exit at the close 20 sessions later.
William P Scully (10% owner) filed 15 Form 4 reports in the trailing twelve months (15 purchases, 0 sales), most often in Prothena Corporation plc (PRTA). Across 13 priced purchase filings, the average 21-session return was +2.1% from execution and -0.6% from disclosure (delay-adjusted; derived). The largest single filing was $1.8M of PRTA (215,000 sh across 2 lots, as filed), executed Oct 7.
Healthcare · Prothena Corporation plc, a late-stage clinical biotechnology company, focuses on discovery and development of novel therapies to treat dis…
More Healthcare filings→ Insider filings, newest first→ View the original filing at www.sec.gov→150,000 sh across 2 lots
Exec Oct 22
Filed Oct 26 · 4:20 PM ET PRTAPURCHASE Prothena Corporation plc $835K
100,000 sh × $8.35
Exec Oct 13
Filed Oct 15 · 4:21 PM ET PRTAPURCHASE Prothena Corporation plc $1.8M
215,000 sh across 2 lots
Exec Oct 7
Filed Oct 9 · 9:43 AM ET PRTAPURCHASE Prothena Corporation plc $857K
100,000 sh × $8.57
Exec Oct 2
Filed Oct 6 · 1:53 PM ET PRTAPURCHASE Prothena Corporation plc $1.4M
162,000 sh × $8.68
Exec Sep 29
Filed Sep 30 · 5:10 PM ET PRTAPURCHASE Prothena Corporation plc $890K
103,500 sh × $8.60
Exec Sep 28
Filed Sep 29 · 5:37 PM ET PRTAPURCHASE Prothena Corporation plc $843K
100,000 sh × $8.43
Exec Sep 18
Filed Sep 21 · 4:23 PM ET PRTAPURCHASE Prothena Corporation plc $256K
27,000 sh × $9.47
Exec Sep 2
Filed Sep 3 · 6:23 PM ET