Figures computed from official regulatory filings — .
Analysttarget 21.4 USD (+156%) · consensus 3.5/5 · 3 buy · 2 hold · 1 sell
Ownershipinsiders 22.35% · institutions 93.9% · short 20.1% of float
In USD · as of Oct 5, 2026
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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.
Market information source · Oct 5, 2026
Periods recorded in the consulted sources. These do not certify the legal dates of name changes.
SEC company identity · Oct 5, 2026
Open-market timeline · full history
36 buys403 sells— close pricebar = usd volume, √ scaleclick a period to filter the table
| Insider | Type | Value · USD | Signals | Details |
|---|---|---|---|---|
| SCULLY WILLIAM Ptrack record | Buy | $1.4M | conv 64 |
| SEC |
| SCULLY WILLIAM Ptrack record | Buy | $889.9K | conv 56 | SEC |
| SCULLY WILLIAM Ptrack record | Buy | $843.5K | conv 37 | SEC |
| SCULLY WILLIAM Ptrack record | Buy | $255.7K | conv 19 | SEC |
| SCULLY WILLIAM Ptrack record | Buy | $439.4K | conv 26 | SEC |
| SCULLY WILLIAM Ptrack record | Gift | n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise)) | SEC |
| SCULLY WILLIAM Ptrack record | Gift | n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise)) | SEC |
| SCULLY WILLIAM Ptrack record | Gift | n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise)) | SEC |
| SCULLY WILLIAM Ptrack record | Buy | $293.1K | conv 26 | SEC |
| SCULLY WILLIAM Ptrack record | Buy | $30.2K | conv 26 | SEC |
| Kinney Gene G. | ExerciseD (derivative) | n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise)) | SEC |
| Nguyen Tran | ExerciseD (derivative) | n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise)) | SEC |
| Walker Karin L | Other | $128.4K | SEC |
| Zago Wagner M. | Exercise | n/a (No price was disclosed in the filing) | SEC |
| Kingston Anne Evans | Sell | $64.9K | SEC |
| Nguyen Tran | Exercise | n/a (No price was disclosed in the filing) | SEC |
| Zago Wagner M. | ExerciseD (derivative) | n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise)) | SEC |
| Swanson Chad J. | ExerciseD (derivative) | n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise)) | SEC |
| Nguyen Tran | Other | $487.9K | SEC |
| Swanson Chad J. | Other | $29.7K | SEC |
| Swanson Chad J. | Exercise | n/a (No price was disclosed in the filing) | SEC |
| Kinney Gene G. | Exercise | n/a (No price was disclosed in the filing) | SEC |
| Smith Brandon S. | ExerciseD (derivative) | n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise)) | SEC |
| Kinney Gene G. | Other | $719K | SEC |
| Walker Karin L | ExerciseD (derivative) | n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise)) | SEC |