Boxer Capital PRTA Position
Exited5-Fund ConvergenceBoxer Capital exited their position in Prothena Corporation plc (PRTA) in Q4 2024, after holding the stock for 12 quarters.
The position was first reported in Q1 2022 and has been tracked across 12 quarterly 13F filings.
PRTA is a convergence signal: 5 specialist biotech funds hold this stock, suggesting high institutional conviction.
Short interest stands at 15.6% of float with 13.4 days to cover, indicating significant bearish positioning against the stock.
About Prothena Corporation plc
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.
Full company profile →Short Interest
15.6%
13.4 days to cover
Boxer Capital PRTA Position History
| Quarter | Action | Shares | Change | Value |
|---|---|---|---|---|
| Q4 2024 | Exited | 0 | -690,000 | $0 |
| Q3 2024 | Held | 690,000 | — | $11.5M |
| Q2 2024 | Held | 690,000 | — | $14.2M |
| Q1 2024 | Increased | 690,000 | +25,000 | $17.1M |
| Q4 2023 | Increased | 665,000 | +40,000 | $24.2M |
| Q3 2023 | Increased | 625,000 | +325,000 | $30.2M |
| Q2 2023 | Held | 300,000 | — | $20.5M |
| Q1 2023 | Held | 300,000 | — | $14.5M |
| Q4 2022 | Held | 300,000 | — | $18.1M |
| Q3 2022 | Held | 300,000 | — | $18.2M |
| Q2 2022 | Held | 300,000 | — | $8.1M |
| Q1 2022 | New | 300,000 | +300,000 | $11.0M |
Frequently Asked Questions
Does Boxer Capital own PRTA?
No. Boxer Capital exited their position in Prothena Corporation plc (PRTA) in Q4 2024. They previously held the stock for 12 quarters.
How many hedge funds own PRTA?
5 specialist biotech hedge funds currently hold PRTA, including EcoR1 Capital, Rock Springs Capital, Eventide Asset Management and 2 more. When 3 or more specialist funds hold the same stock, BiotechEdge flags it as a convergence signal.
When did Boxer Capital first buy PRTA?
Boxer Capital's position in PRTA was first reported in Q1 2022. 13F filings are reported with a 45-day delay, so the actual purchase may have occurred earlier in the quarter.
Is Boxer Capital's PRTA position increasing or decreasing?
Boxer Capital completely exited their PRTA position in the most recent quarter.
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