Prothena 10% Owner William P. Scully Reports Acquisition of $1.22 Million in Common Shares

• Prothena 10% owner William P. Scully purchased 150,000 ordinary shares, par value $0.01 per share.
• Purchases comprised 100,000 shares at $8.1852 each and 50,000 shares at $8.0705 each.
• Direct holdings rose to 1,187,000 shares. Indirect holdings included 529,000 shares through his spouse and 187,000 through Manatee Equity Fund.

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