Prothena 10% owner William P. Scully buys USD 890,874 of common shares

• William P. Scully, a 10% owner of Prothena, reported an indirect purchase of 103,500 ordinary shares.
• The shares were bought at a weighted average price of $8.5978.
• Indirect holdings via Manatee Equity Fund LLC rose to 187,000 ordinary shares.
• He also reported direct ownership of 927,000 ordinary shares.
• An additional 52,000 ordinary shares were reported as indirectly owned by his spouse.

Disclaimer: This news brief was created by Public Technologies (PUBT) using generative artificial intelligence. While PUBT strives to provide accurate and timely information, this AI-generated content is for informational purposes only and should not be interpreted as financial, investment, or legal advice. Prothena Corporation plc published the original content used to generate this news brief via EDGAR, the Electronic Data Gathering, Analysis, and Retrieval system operated by the U.S. Securities and Exchange Commission (Ref. ID: 0001045463-26-000017), on September 29, 2026, and is solely responsible for the information contained therein.