Prothena (NASDAQ:PRTA) Major Shareholder William Scully Acquires 125,000 Shares of Stock

Posted by George Bondi on Jun 13th, 2026

Prothena Corporation plc (NASDAQ:PRTA – Get Free Report) major shareholder William Scully purchased 125,000 shares of the stock in a transaction on Thursday, June 11th. The stock was acquired at an average cost of $8.17 per share, for a total transaction of $1,021,250.00. Following the acquisition, the insider owned 1,061,000 shares in the company, valued at approximately $8,668,370. This represents a 13.35% increase in their ownership of the stock. The acquisition was disclosed in a filing with the SEC, which is available through this link. Large shareholders that own at least 10% of a company’s stock are required to disclose their sales and purchases with the SEC.

Prothena Stock Down 0.1%

NASDAQ:PRTA opened at $8.25 on Friday. The business’s 50-day moving average price is $9.99 and its two-hundred day moving average price is $9.64. Prothena Corporation plc has a twelve month low of $4.95 and a twelve month high of $11.80. The stock has a market cap of $431.89 million, a P/E ratio of -2.93, a PEG ratio of 1.32 and a beta of -0.25.

Prothena (NASDAQ:PRTA – Get Free Report) last released its quarterly earnings results on Thursday, May 7th. The biotechnology company reported $0.60 earnings per share for the quarter, beating the consensus estimate of ($0.31) by $0.91. Prothena had a negative return on equity of 43.44% and a negative net margin of 260.92%.The firm had revenue of $51.08 million for the quarter, compared to analysts’ expectations of $0.81 million. On average, equities research analysts expect that Prothena Corporation plc will post 0.18 EPS for the current fiscal year.

Analyst Ratings Changes

A number of equities analysts recently weighed in on the company. Stifel Nicolaus set a $19.00 price objective on Prothena in a report on Friday, March 13th. Royal Bank Of Canada raised their price objective on Prothena from $11.00 to $12.00 and gave the company a “sector perform” rating in a report on Friday, February 20th. Wall Street Zen raised Prothena from a “hold” rating to a “buy” rating in a report on Saturday, June 6th. Citigroup reissued an “outperform” rating on shares of Prothena in a report on Friday, May 8th. Finally, Citizens Jmp raised their price objective on Prothena from $19.00 to $20.00 and gave the company a “market outperform” rating in a report on Friday, May 8th. One analyst has rated the stock with a Strong Buy rating, four have given a Buy rating, two have issued a Hold rating and one has issued a Sell rating to the company’s stock. Based on data from MarketBeat, the company currently has a consensus rating of “Moderate Buy” and a consensus target price of $23.75.

Check Out Our Latest Report on Prothena

Institutional Investors Weigh In On Prothena

Large investors have recently made changes to their positions in the business. JPMorgan Chase & Co. grew its position in shares of Prothena by 479.6% in the 3rd quarter. JPMorgan Chase & Co. now owns 735,765 shares of the biotechnology company’s stock worth $7,181,000 after buying an additional 608,814 shares during the last quarter. Focused Wealth Management Inc grew its position in shares of Prothena by 88.1% in the 4th quarter. Focused Wealth Management Inc now owns 107,479 shares of the biotechnology company’s stock worth $1,026,000 after buying an additional 50,350 shares during the last quarter. Hennion & Walsh Asset Management Inc. grew its position in shares of Prothena by 7.9% in the 4th quarter. Hennion & Walsh Asset Management Inc. now owns 91,284 shares of the biotechnology company’s stock worth $872,000 after buying an additional 6,686 shares during the last quarter. DCF Advisers LLC grew its position in shares of Prothena by 28.3% in the 3rd quarter. DCF Advisers LLC now owns 200,747 shares of the biotechnology company’s stock worth $1,959,000 after buying an additional 44,247 shares during the last quarter. Finally, Fox Run Management L.L.C. bought a new stake in shares of Prothena in the 3rd quarter worth approximately $433,000. 97.08% of the stock is currently owned by institutional investors.

About Prothena

(Get Free Report)

Prothena Corporation plc is a clinical-stage biotechnology company dedicated to the discovery and development of novel therapies for neurodegenerative and rare diseases driven by misfolded proteins. The company’s research focuses on immunotherapies and small molecules designed to target and clear disease-causing protein aggregates. Prothena leverages proprietary protein engineering and antibody discovery platforms to advance candidates through preclinical and clinical stages.

The company’s most advanced program is an antibody targeting aggregated alpha-synuclein for the potential treatment of Parkinson’s disease, currently in mid-stage clinical trials.