PRTA - NASDAQ
Prothena Corporation plc
$9.19
-2.9%Prothena Corporation plc, a late-stage clinical company, focuses on discovery and development of novel therapies for life-threatening diseases in the United States. The company is involved in developing Birtamimab, an investigational humanized antibody that is in Phase III clinical trial for the treatment of AL amyloidosis; Prasinezumab, a humanized monoclonal antibody, which is in Phase IIb clinical trial for the treatment of Parkinson's disease; PRX004 that completed Phase I clinical trial for the treatment of Transthyretin amyloidosis; and PRX005, which is in Phase I clinical trial for the treatment of Alzheimer's disease. Its discovery and preclinical programs include PRX012 for the treatment of Alzheimer's disease; and dual Aß-Tau vaccine for the treatment and prevention of Alzheimer's disease. Prothena Corporation plc 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 alpha-synuclein; and a collaboration agreement with Bristol-Myers Squibb to develop antibodies. The company was founded in 2012 and is based in Dublin, Ireland.
At a Glance
Live SnapshotProthena Corporation plc Management Team
Karin L. Walker
Chief Accounting Officer & Controller
Chad Swanson
Chief Development Officer
Compensation
$739,084
Tran Nguyen
Chief Financial Officer
Compensation
$916,334
Michael J. Malecek
Chief Legal Officer & Company Secretary
Compensation
$588,250
Brandon S. Smith
Chief Operating Officer
Compensation
$826,819
Wagner Zago
Chief Scientific Officer
Compensation
$735,660
Annie Evans Kingston
Chief Strategy Officer
Gene G. Kinney
President, Chief Executive Officer & Director
Compensation
$1,124,507
Phillip Dolan
Sr. Director & Head of Exploratory Research
Mark C. Johnson
Vice President of Investor Relations
Prothena Corporation plc Insider Positioning
During the last 12 months, insiders have purchased $1.45M worth of PRTA shares, with no selling activity reported.
3 Months
150.0K
1.45M
0
0.00
+1.5M
+$1.45M
3-6 Months
0
0.00
0
0.00
+0
+$0
6-9 Months
0
0.00
0
0.00
+0
+$0
9-12 Months
0
0.00
0
0.00
+0
+$0
Top Buyers
Scully William P
10 Percent Owner
$1.45M
Top Sellers
No selling activity
Insider Activity Analysis
Net Insider Sentiment
Strong bullish signal with $1.45M net buying. Insiders are aggressively accumulating shares, suggesting significant confidence in future prospects.
Buy/Sell Ratio
Perfect buy/sell ratio. Only buying activity with zero selling—the most bullish possible insider signal.
Recent Trend (3 Months)
Very strong recent buying momentum. Recent insider purchases significantly outpace sales, suggesting near-term optimism.
Insider Participation
1 insider buyers vs. 0 sellers. Broad-based buying across management team suggests widespread confidence.
Insider Activity Insight
Unanimous insider buying: Zero selling combined with active buying is rare and typically very bullish. Insiders appear to see significant upside with limited downside risk.
SEC Filings
PRTA - Filing history and reports
| Filing Type | Filing Date | Period Ending | Fiscal Year | Actions |
|---|---|---|---|---|
DEF 14A DEF 14A 2026 N/A | March 27, 2026 | May 14, 2026 | 2026 | |
DEF 14A DEF 14A 2025 N/A | October 07, 2025 | November 19, 2025 | 2025 | |
DEF 14A DEF 14A 2025 N/A | March 28, 2025 | May 13, 2025 | 2025 | |
DEF 14A DEF 14A 2024 N/A | March 29, 2024 | May 14, 2024 | 2024 | |
DEF 14A DEF 14A N/A | March 31, 2023 | March 31, 2023 | ||
DEF 14A DEF 14A 2022 N/A | March 31, 2022 | May 17, 2022 | 2022 | |
DEF 14A DEF 14A 2021 N/A | March 31, 2021 | May 18, 2021 | 2021 | |
DEF 14A DEF 14A 2020 N/A | March 25, 2020 | May 19, 2020 | 2020 | |
DEF 14A DEF 14A 2019 N/A | March 28, 2019 | May 21, 2019 | 2019 | |
DEF 14A DEF 14A 2018 N/A | March 29, 2018 | May 15, 2018 | 2018 |
Research Paths
Snapshot
Start with context, operating signals, and key market metrics.
Value Model
Stress test fair value across bear, base, and bull assumptions.
Statements
Validate revenue quality, margins, and balance sheet durability.
Earnings Call
Read management commentary and compare it with reported outcomes.
Dividends
Check payout sustainability and long-term distribution behavior.
Analyst Expectations
Review consensus spread and where estimate risk is concentrated.