Welcome to our dedicated page for Prothena SEC filings (Ticker: PRTA), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
The Prothena Corporation plc (NASDAQ: PRTA) SEC filings page on Stock Titan brings together the company’s regulatory disclosures from the U.S. Securities and Exchange Commission, alongside AI-powered summaries designed to make these documents easier to understand. Prothena is an Irish public limited company whose ordinary shares trade on The Nasdaq Global Select Market, and it files reports such as Forms 8-K and proxy statements in connection with material events and shareholder meetings.
Recent 8-K filings referenced by the company include disclosures about quarterly financial results, workforce reductions following the discontinuation of the birtamimab program, collaboration developments such as Novo Nordisk advancing coramitug (formerly PRX004) for ATTR amyloidosis with cardiomyopathy, and updates on the PRX012 Phase 1 ASCENT clinical program. Other 8-Ks describe governance and compensation matters, including employment agreements for senior officers and the planned resignation of a Board member, as well as the outcome of an Extraordinary General Meeting where shareholders approved a reduction of capital to create distributable reserves.
Prothena’s definitive proxy statement for the Extraordinary General Meeting explains the rationale for the capital reduction and outlines voting procedures for shareholders of the Irish public limited company. These filings, together with the company’s periodic reports referenced in its press releases, form the official record of Prothena’s financial condition, capital structure decisions, and key operational events.
On Stock Titan, users can access Prothena’s SEC filings as they are made available through EDGAR and use AI-generated highlights to quickly identify the main points in lengthy documents. For PRTA, this can include understanding how collaboration revenue from partners like Bristol Myers Squibb is reported, how restructuring charges are described, and how shareholder approvals are documented in connection with potential share redemption programs and other capital management actions.
Prothena Corporation plc has called its 2026 annual general meeting for May 14, 2026 in Dublin. Shareholders will vote on re‑electing directors Shane M. Cooke and Dennis J. Selkoe, ratifying KPMG LLP as auditor, and approving 2025 executive pay in an advisory “say‑on‑pay” vote.
Only holders of the company’s 53,832,982 ordinary shares as of March 2, 2026 may vote, one vote per share, with a simple majority of votes cast required for each proposal. The proxy details extensive governance practices, director independence, and committee structures.
The filing also reviews 2025 performance: termination of birtamimab after a failed Phase 3 trial and a workforce reduction of about 63%, alongside progress in partnered late‑stage programs with Roche, Novo Nordisk, and Bristol Myers Squibb. Prothena reports cash used in operating and investing activities of $163.7M, better than guidance, and year‑end liquidity of $308.4M, above a $298.0M target.
Zago Wagner M. reported acquisition or exercise transactions in this Form 4 filing.
PROTHENA CORP PUBLIC LTD CO reported that Chief Scientific Officer Zago Wagner M. was granted a stock option covering 190,000 shares of the company’s stock. The option was reported at a grant price of $0.00 per share and is held as direct ownership.
According to the vesting terms, 25% of the total shares under the option will vest and become exercisable on March 3, 2027. The remaining shares will vest in 1/48th increments in equal monthly installments on each monthly anniversary after that date, conditioned on Wagner’s continued employment with the company on each vesting date.
PROTHENA CORP PUBLIC LTD CO reported that Chief Accounting Officer Karin L. Walker acquired a stock option covering 150,000 shares of the company’s stock. This option was reported as a grant or award acquisition in a Form 4 insider filing.
According to the vesting terms, 25% of the 150,000 shares subject to the option will vest and become exercisable on March 3, 2027. The remaining portion will vest in 1/48th increments in equal monthly installments on each monthly anniversary after that date, conditioned on Ms. Walker’s continued employment with the company on each vesting date.
PROTHENA CORP PUBLIC LTD CO reported that Chief Development Officer Chad J. Swanson acquired a grant of 190,000 stock options on March 3, 2026. The options were awarded at no cost as a “Stock Option (Right to Buy).”
According to the vesting terms, 25% of the total options will vest and become exercisable on March 3, 2027. The remaining options will vest in equal monthly installments of 1/48th of the total number of shares on each monthly anniversary thereafter, subject to his continued employment with the company on each vesting date.
PROTHENA CORP PUBLIC LTD CO granted Chief Operating Officer Brandon S. Smith a stock option covering 190,000 shares on March 3, 2026. This option was reported as a direct, derivative security and classified as a grant or award acquisition.
According to the vesting terms, 25% of the shares underlying the option will vest and become exercisable on March 3, 2027. The remaining shares will vest in 1/48th monthly installments on each monthly anniversary thereafter, conditioned on Smith’s continued employment with the company on each vesting date.
Nguyen Tran reported acquisition or exercise transactions in this Form 4 filing.
PROTHENA CORP PUBLIC LTD CO granted Nguyen Tran, its Chief Strategy Officer and CFO, a stock option covering 230,000 shares. The option vests as to 25% of the shares on March 3, 2027, with the remaining 75% vesting in equal monthly installments over the following three years, subject to continued employment.
Malecek Michael J reported acquisition or exercise transactions in this Form 4 filing.
Prothena Corp Public Ltd Co granted Chief Legal Officer Michael J. Malecek a stock option covering 190,000 shares of the company’s stock. According to the award terms, 25% of the option will vest and become exercisable on March 3, 2027. The remaining shares will vest in equal monthly installments of 1/48th of the total option on each monthly anniversary thereafter, subject to his continued employment with the company on each vesting date.
Kinney Gene G. reported acquisition or exercise transactions in this Form 4 filing.
PROTHENA CORP PUBLIC LTD CO reported that President and CEO Gene G. Kinney received a grant of stock options covering 520,000 shares on March 3, 2026. These options vest as to 25% of the total shares on March 3, 2027, then in equal monthly installments of 1/48th of the total shares on each monthly anniversary thereafter, subject to his continued employment with the company.
Prothena Corporation plc announced that its board has authorized a share repurchase plan allowing the company to buy back up to $100.0 million of its outstanding ordinary shares. The plan runs through December 31, 2026, is fully discretionary, and can be suspended or ended at any time.
Prothena reported $308.4 million in cash, cash equivalents and restricted cash and no debt as of December 31, 2025, and expects to end 2026 with about $255 million in cash excluding any repurchases. The company also highlights potential to earn up to $105 million in 2026 clinical milestone payments from strategic partners Novo Nordisk and Bristol Myers Squibb.