William P Scully insider trades: Prothena Corp Public (PRTA) stock buys and sales
Trades on the price chart
Daily close, with an arrow on each day they bought or sold
Companies
Where William reports to the SEC
Open-market buys and sales
23 trades reported on SEC Form 4, newest first
| Date | Stock | Type | Shares | Price | Value | Holding | Reported |
|---|---|---|---|---|---|---|---|
| Oct 23, 2026 | PRTA | ↑ Buy | 150,000 | $8.15 | $1.2M | Direct | Oct 26, 2026 (3d) |
| Oct 14, 2026 | PRTA | ↑ Buy | 110,000 | $8.36 | $920K | Direct | Oct 15, 2026 (1d) |
| Oct 2, 2026 | PRTA | ↑ Buy | 100,000 | $8.57 | $857K | By Spouse | Oct 6, 2026 (4d) |
| Sep 29, 2026 | PRTA | ↑ Buy | 162,000 | $8.68 | $1.4M | By Spouse | Sep 30, 2026 (1d) |
| Sep 28, 2026 | PRTA | ↑ Buy | 103,500 | $8.60 | $890K | By Manatee Equity Fund LLC | Sep 29, 2026 (1d) |
| Sep 18, 2026 | PRTA | ↑ Buy | 100,000 | $8.43 | $843K | Direct | Sep 21, 2026 (3d) |
| Sep 2, 2026 | PRTA | ↑ Buy | 27,000 | $9.47 | $256K | Direct | Sep 3, 2026 (1d) |
| Aug 20, 2026 | PRTA | ↑ Buy | 50,000 | $8.79 | $439K | Direct | Aug 21, 2026 (1d) |
| Aug 7, 2026 | PRTA | ↑ Buy | 34,000 | $8.62 | $293K | Direct | Aug 10, 2026 (3d) |
| Aug 7, 2026 | PRTA | ↑ Buy | 3,500 | $8.62 | $30K | By Manatee Equity Fund LLC | Aug 10, 2026 (3d) |
| Jun 16, 2026 | PRTA | ↑ Buy | 20,000 | $7.90 | $158K | Direct | Jun 18, 2026 (2d) |
| Jun 11, 2026 | PRTA | ↑ Buy | 125,000 | $8.17 | $1.0M | Direct | Jun 12, 2026 (1d) |
| Jun 2, 2026 | PRTA | ↑ Buy | 50,000 | $9.43 | $471K | Direct | Jun 3, 2026 (1d) |
| May 22, 2026 | PRTA | ↑ Buy | 100,000 | $9.81 | $981K | Direct | May 26, 2026 (4d) |
| Jan 14, 2025 | PRTA | ↑ Buy | 207,436 | $13.26 | $2.7M | Direct | May 2, 2025 (108d) |
| Sep 13, 2016 | MBLX | ↓ Sell | 68,333 | $0.33 | $23K | Direct | Sep 14, 2016 (1d) |
| Sep 9, 2016 | MBLX | ↓ Sell | 165,000 | $0.35 | $57K | Direct | Sep 12, 2016 (3d) |
| Sep 17, 2015 | MBLX | ↑ Buy | 31,833 | $2.11 | $67K | Direct | Sep 21, 2015 (4d) |
| Sep 15, 2015 | MBLX | ↑ Buy | 67,500 | $2.16 | $146K | Direct | Sep 16, 2015 (1d) |
| Sep 10, 2015 | MBLX | ↑ Buy | 25,000 | $2.71 | $68K | Direct | Sep 14, 2015 (4d) |
| Sep 8, 2015 | MBLX | ↑ Buy | 40,000 | $2.23 | $89K | Direct | Sep 10, 2015 (2d) |
| Sep 4, 2015 | MBLX | ↑ Buy | 42,750 | $2.15 | $92K | Direct | Sep 8, 2015 (4d) |
| Aug 28, 2015 | MBLX | ↑ Buy | 26,600 | $1.99 | $53K | Direct | Sep 1, 2015 (4d) |
Each row is one filing's trades in one stock, summed. Shares and prices are as filed, before any later stock split.
Other PRTA insiders
Open-market trades in the last 12 months
About William P Scully's insider trades
William P Scully is a 10% owner of Prothena Corp Public (PRTA). Since Aug 28, 2015, William has reported 21 open-market purchases worth $13.1M and 2 sales worth $80K on SEC Form 4. In the last 12 months: 14 buys ($9.8M).
Their filings also include gifts (4 filings), conversions (1 filing). These aren't open-market trades and aren't counted above.
How to read insider trades
Officers, directors and owners of more than 10% of a company must report trades in its stock on SEC Form 4, usually within two business days. Purchases with their own money are the stronger signal: insiders sell for many reasons (taxes, diversification, a house), but buy for one. See every PRTA insider trade, the latest insider trades across the market, or cluster buys, when several insiders buy the same stock within days.