10% Owner William Scully Buys $1.19 Million of Prothena Stock
The purchase, at $8.53 a share, left Scully with 977,000 shares held directly after the trade.
Prothena Corp Public PRTA
Prothena Corp Public Ltd Co · Nasdaq · Pharmaceutical Preparations
$8.23-5.73%close on Nov. 12, 2026 · volume 237K · Yahoo Finance
Price, last 58 sessions
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Insider buying and selling
| Date | Insider | Trade | Shares | Avg. price | Value |
|---|---|---|---|---|---|
| Nov. 9, 2026 | William P. Scully 10% owner | Bought | 140,000 | $8.53 | $1.19 million |
| Oct. 23, 2026 | William P. Scully 10% owner | Bought | 50,000 | $8.07 | $403,525 |
| Oct. 22, 2026 | William P. Scully 10% owner | Bought | 100,000 | $8.19 | $818,520 |
| Oct. 14, 2026 | William P. Scully 10% owner | Bought | 10,000 | $8.46 | $84,569 |
| Oct. 13, 2026 | William P. Scully 10% owner | Bought | 100,000 | $8.35 | $835,480 |
| Oct. 8, 2026 | William P. Scully 10% owner · indirect | Bought | 90,000 | $8.57 | $770,904 |
| Oct. 7, 2026 | William P. Scully 10% owner · indirect | Bought | 125,000 | $8.40 | $1.05 million |
| Oct. 2, 2026 | William P. Scully 10% owner · indirect | Bought | 100,000 | $8.57 | $857,240 |
| Sept. 29, 2026 | William P. Scully 10% owner · indirect | Bought | 162,000 | $8.68 | $1.41 million |
| Sept. 28, 2026 | William P. Scully 10% owner · indirect | Bought | 103,500 | $8.60 | $889,872 |
| Sept. 18, 2026 | William P. Scully 10% owner | Bought | 100,000 | $8.43 | $843,460 |
| Sept. 2, 2026 | William P. Scully 10% owner | Bought | 27,000 | $9.47 | $255,739 |
Latest 12 of 17. Open-market purchases and sales reported on SEC Form 4 filed since July 24, 2026; grants, option exercises and shares withheld for tax aren't shown. A trade under a 10b5-1 plan was scheduled in advance. Where a filing was amended, the amendment's figures are shown.
Recent SEC filings
All 33 →Results of operations and financial condition · Financial statements and exhibits
AI summary, unreviewedProthena Reports Q3 2026 Net Loss of $0.32 Per Share, Revenue of $0.6 Million, Missing Consensus; Reiterates 2026 Cash Burn Guidance
Termination of a material definitive agreement · Financial statements and exhibits
AI summary, unreviewedProthena Corporation plc: Bristol Myers Squibb terminates PRX019 license, removing $80 million upfront-linked economics and up to $617.5 million in potential milestones