William P. Scully, a 10% owner of Prothena Corp Public Ltd Co (PRTA), acquired 140,000 shares of the company on November 9, 2026, for approximately $1.19 million. The shares were purchased at an average price of $8.53 each.
This significant transaction follows several other purchases made by Mr. Scully in recent weeks, totaling over 350,000 shares. Such substantial insider buying activity is often interpreted as a signal of strong confidence in the company's future performance and prospects.