Investors can expect a company’s stock to rise or fall based on the buying and selling of stock by its insiders. Prothena Corporation plc shares valued at $27,744,929 were sold by EcoR1 Capital, LLC on May 02 ’25. At $8.36 per share, EcoR1 Capital, LLC sold 3,317,938 shares. The insider’s holdings dropped to 8,266,342 shares worth approximately $52.24 million following the completion of this transaction.
Also, EcoR1 Capital, LLC sold 1,984,053 shares, netting a total of over 15,164,712 in proceeds. Following the sale of shares at $7.64 each, the insider now holds 5,304,596 shares.
Before that, EcoR1 Capital, LLC had sold 977,693 shares from its account. In a trade valued at $7,930,166, the 10% Owner traded Prothena Corporation plc shares for $8.11 each. Upon closing the transaction, the insider’s holdings decreased to 977,693 shares, worth approximately $46.06 million.
As published in a research note from BofA Securities on May 28, 2025, Prothena Corporation plc [PRTA] has been rated down from a Neutral to an Underperform and the price target has been revised to $4. Analysts at Oppenheimer downgraded the stock from ‘”an Outperform”‘ to ‘”a Perform”‘ outlook in a report released in late May. As of May 27, 2025, Jefferies has decreased its “Buy” rating to a “Hold” for PRTA. Earlier on May 27, 2025, Cantor Fitzgerald downgraded its rating. Their new recommendation was “a Neutral” for PRTA stock which previously was a “an Overweight”.
Analyzing PRTA Stock Performance
On last trading session,, Prothena Corporation plc [NASDAQ: PRTA] rose 0.96% to $6.32. The stock’s lowest price that day was $6.13, but it reached a high of $6.585 in the same session. During the last five days, there has been a surge of approximately 5.51%. Over the course of the year, Prothena Corporation plc shares have dropped approximately -69.38%. Shares of the company reached a 52-week high of $16.67 on 02/21/25 and a 52-week low of $4.32 on 05/28/25.
Support And Resistance Levels for Prothena Corporation plc (PRTA)
According to the 24-hour chart, there is a support level at 6.11, which, if violated, would cause prices to drop to 5.89. In the upper region, resistance lies at 6.56. The next price resistance is at 6.80. RSI (Relative Strength Index) is 55.78 on the 14-day chart, showing neutral technical sentiment.
Is Prothena Corporation plc subject to short interest?
Stocks of Prothena Corporation plc saw a sharp steep in short interest on 2025-06-13 dropping by -4.3 million shares to 4.66 million. Data from Yahoo Finance shows that the short interest on 2025-05-15 was 8.95 million shares. A decline of -92.29% in short interest reflects a positive sentiment towards the stock. Despite the fact that short shares comprise just 2.24 of the overall float, the days-to-cover ratio (short ratio) decline to 2.24.
Which companies own the most shares of Prothena Corporation plc (PRTA)?
In terms of Prothena Corporation plc share price expectations, FactSet research, analysts set an average price target of 56 in the next 12 months, up nearly 794.57% from the previous closing price of $6.26. Analysts anticipate Prothena Corporation plc stock to reach 98 by 2025, with the lowest price target being 24. In spite of this, 15 analysts ranked Prothena Corporation plc stock as Buy at the end of 2025. On December 20, 2024, Chardan Capital Markets assigned a price target of “a Buy” to the stock and initiated coverage with a $40.
