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PRTA NASDAQ

Prothena Corporation plc
1W: -4.6% 1M: -12.2% 3M: +4.3% YTD: +2.3% 1Y: +29.1% 3Y: -87.2% 5Y: -59.0%
$9.83
+0.42 (+4.46%)
 
Weekly Expected Move ±8.3%
$8 $9 $10 $11 $11
NASDAQ · Healthcare · Biotechnology · Alpha Radar Sell · Power 31 · $514.6M mcap · 42M float · 1.24% daily turnover · Short 68% of daily vol

🏦 Institutional Activity

Latest: Q1 2026
208
Institutions Holding
-5 vs prior
64.0%
Ownership
-20.72%
27 New
61 Increased
85 Reduced
42 Closed

👔 Insider Trades

23 records
Date Name Title Type Shares Price Value Filing
2025-07-28 Kinney Gene G. officer: president and ceo A-Grant/Award 140,000 $— $0 Filing
2025-07-28 Malecek Michael J officer: chief legal officer A-Grant/Award 80,000 $— $0 Filing
2025-07-28 Nguyen Tran officer: chief strategy officer and cfo A-Grant/Award 95,000 $— $0 Filing
2025-07-28 Smith Brandon S. officer: chief operating officer A-Grant/Award 130,000 $— $0 Filing
2025-07-28 Swanson Chad J. officer: chief development officer A-Grant/Award 85,000 $— $0 Filing
2025-07-28 Walker Karin L officer: chief accounting officer A-Grant/Award 25,000 $— $0 Filing
2025-07-28 Zago Wagner M. officer: chief scientific officer A-Grant/Award 85,000 $— $0 Filing
2025-05-06 EcoR1 Capital, LLC 10% owner S-Sale 1,984,053 $7.64 $15.2M Filing
2025-05-05 EcoR1 Capital, LLC 10% owner S-Sale 977,693 $8.11 $7.9M Filing
2025-05-02 EcoR1 Capital, LLC 10% owner S-Sale 3,317,938 $8.36 $27.7M Filing
2025-01-15 SCULLY WILLIAM P 10% owner G-Gift 12,000 $— $0 Filing
2025-01-14 SCULLY WILLIAM P 10% owner P-Purchase 100,000 $12.79 $1.3M Filing
2025-01-03 SCULLY WILLIAM P 10% owner G-Gift 1,000 $— $0 Filing
2025-01-02 SCULLY WILLIAM P 10% owner G-Gift 13,200 $— $0 Filing
2024-12-31 SCULLY WILLIAM P 10% owner P-Purchase 1,200 $13.37 $16K Filing
2024-12-31 SCULLY WILLIAM P 10% owner P-Purchase 800 $13.39 $11K Filing
2024-12-31 SCULLY WILLIAM P 10% owner P-Purchase 30,000 $12.99 $390K Filing
2024-12-20 SCULLY WILLIAM P 10% owner P-Purchase 2,000 $15.91 $32K Filing
2024-12-20 SCULLY WILLIAM P 10% owner G-Gift 500 $— $0 Filing
2024-12-20 SCULLY WILLIAM P 10% owner G-Gift 40,000 $— $0 Filing
2024-12-19 SCULLY WILLIAM P 10% owner G-Gift 681,000 $— $0 Filing
2024-12-18 SCULLY WILLIAM P 10% owner G-Gift 430,000 $— $0 Filing
2024-12-18 SCULLY WILLIAM P 10% owner P-Purchase 73,436 $13.93 $1.0M Filing

🏛️ Congressional Trades

0 records
Date Politician Chamber Type Amount Filing
No congressional trades found

🏦 Top Institutional Holders

20 holders
Holder Shares Value Date Reported Filing
FMR LLC 7,551,218 $73M 2026-03-31 Filing
BlackRock, Inc. 4,644,160 $45M +536,701 2026-03-31 Filing
STATE STREET CORP 1,938,498 $19M -329,304 2026-03-31 Filing
ADAR1 Capital Management, LLC 1,581,443 $15M +123,679 2026-03-31 Filing
VANGUARD PORTFOLIO MANAGEMENT LLC 1,445,979 $14M +1,445,979 2026-03-31 Filing
Palo Alto Investors LP 1,208,568 $12M -111,942 2026-03-31 Filing
GEODE CAPITAL MANAGEMENT, LLC 1,098,166 $11M +35,097 2026-03-31 Filing
JACOBS LEVY EQUITY MANAGEMENT, INC 972,017 $9M -5,994 2026-03-31 Filing
GOLDMAN SACHS GROUP INC 818,885 $8M -116,448 2026-03-31 Filing
DIMENSIONAL FUND ADVISORS LP 782,603 $8M +7,396 2026-03-31 Filing
Nuveen, LLC 759,368 $7M +261 2026-03-31 Filing
Qube Research & Technologies Ltd 614,603 $6M +206,914 2026-03-31 Filing
RENAISSANCE TECHNOLOGIES LLC 607,515 $6M +172,000 2026-03-31 Filing
Mariner, LLC 563,082 $5M -14,856 2026-03-31 Filing
MONIMUS CAPITAL MANAGEMENT, LP 485,617 $5M +231,495 2026-03-31 Filing
VANGUARD CAPITAL MANAGEMENT LLC 484,126 $5M +484,126 2026-03-31 Filing
Rangeley Capital, LLC 449,460 $4M -75,140 2026-03-31 Filing
Birchview Capital, LP 449,019 $4M +8,000 2026-03-31 Filing
ARMISTICE CAPITAL, LLC 439,411 $4M -1,060,589 2026-03-31 Filing
BNP PARIBAS FINANCIAL MARKETS 424,596 $4M +641 2026-03-31 Filing

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For informational purposes only. Not investment advice. Data sourced from SEC filings. Privacy Terms