Timing
Purchase and sale flow
PurchasesSales
Stock, pipeline and biotech catalyst intelligence
Reported ownership activity
Activity signal
Reported purchases exceed sales by $2.8MOption exercises, awards, and grants are separated from open-market direction.Timing
Composition
Concentration
Company profile
Prothena Corporation plc, a late-stage clinical biotechnology company, focuses on discovery and development of novel therapies to treat diseases caused by protein dysregulation. Its product pipeline includes Prasinezumab, an investigational humanized monoclonal antibody which is in Phase 3 clinical trial for the treatment of parkinson's disease and other synucleinopathies. The company also develops Coramitug, an investigational antibody, which is in Phase 3 clinical trial for the treatment of transthyretin amyloidosis; BMS-986446, an anti-tau antibody which is in Phase 2 clinical trial to treat Alzheimer's disease; PRX019, an investigational antibody which is in Phase 1 clinical trial for the treatment of neurodegenerative diseases; and PRX123, a Dual Aß-Tau Vaccine, which is in preclinical trial for treating Alzheimer's disease. In addition, it develops discovery- and late-preclinical-stage programs include TDP-43 CYTOPE for the treatment of amyotrophic lateral sclerosis; PRX012, a next-generation anti-Aß antibody which is in phase 1 clinical trial to treat Alzheimer's disease; and PRX012-TfR, a preclinical program for the treatment of Alzheimer's disease. It has a license, development, and commercialization agreement with F. Hoffmann-La Roche Ltd. and Hoffmann-La Roche Inc. to develop and commercialize antibodies that target a-synuclein, including prasinezumab; and master collaboration agreement with Bristol Myers Squibb to develop and commercialize antibodies targeting tau, TDP-43. Prothena Corporation plc was incorporated in 2012 and is based in Dublin, Ireland.
Company profile supplied by Yahoo Finance. Catalyst dates can change and should be confirmed against the linked primary source.
Page updated Aug 21, 2026 · Yahoo quotes cached for one minute; reference data may be used when a live field is unavailable.
| Insider trading | Relationship | Date | Transaction | Cost | Shares | Value | Shares total | SEC Form 4 |
|---|---|---|---|---|---|---|---|---|
| Scully William P | 10% Owner | Aug 20 '26 | Buy | $8.79 | 50,000 | $439,430 | 800,000 | Aug 21 02:32 PM |
| Scully William P | 10% Owner | Aug 07 '26 | Buy | $8.62 | 34,000 | $293,053 | 790,000 | Aug 10 03:24 PM |
| Scully William P | 10% Owner | Aug 07 '26 | Buy | $8.62 | 3,500 | $30,167 | 83,500 | Aug 10 03:24 PM |
Transactions may include sales, purchases, grants, and option exercises. Directional charts count only purchases and sales; follow the Form 4 link to verify the original SEC filing.