Prothena Corp.PRTA
13F holders, Q1 2026 (March 31)186holders +4
25new positions
22sold out
6famous investors
$9.72avg. 13F price*
At the end of Q1 2026, 186 institutions reported holding Prothena Corp. PLC (PRTA) in their 13F filings, up 4 from Q4 2025. 25 opened new positions and 22 sold out. The largest holders were FMR LLC ($73.4M), Rubric Capital Management LP ($48.6M) and BlackRock, Inc. ($45.1M). 6 famous investors held it, including David E. Shaw (0.0% of D. E. Shaw & Co.'s portfolio), Jim Simons / Peter Brown (0.0% of Renaissance Technologies's portfolio) and Steve Cohen (0.0% of Point72 Asset Management's portfolio).
- Company
- Prothena Corp. PLC
- CUSIP
- G72800108
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q4 2025 → Q1 2026
| Institutions | Total Value | |
|---|---|---|
| New Positions | 25 | $8.1M |
| Exits | 22 | $7.3M |
All 13F filers, Q4 2025 → Q1 2026: 5,124,676 shares bought and 4,731,889 shares sold, net +392,787 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 186 holders
| FMR LLC | 0.00% | No change | 7,551,218 | $73.4M |
| Rubric Capital Management LP | 0.60% | Add +36.0% | 5,000,000 | $48.6M |
| BlackRock, Inc. | 0.00% | Add +13.1% | 4,644,160 | $45.1M |
| State Street Corp. | 0.00% | Reduce -14.5% | 1,938,498 | $18.8M |
| D. E. Shaw & Co. | 0.01% | Add +4.9% | 1,763,347 | $17.1M |
| ADAR1 Capital Management, LLC | 0.93% | Add +8.5% | 1,581,443 | $15.4M |
| Acadian Asset Management LLC | 0.02% | Add +7.7% | 1,547,593 | $15.0M |
| Vanguard Portfolio Management LLC | 0.00% | — | 1,445,979 | $14.1M |
| Morgan Stanley | 0.00% | Reduce -1.3% | 1,230,448 | $12.0M |
| Palo Alto Investors LP | 1.80% | Reduce -8.5% | 1,208,568 | $11.7M |
| Two Sigma Investments, LP | 0.01% | Add +80.0% | 1,205,978 | $11.7M |
| Geode Capital Management, LLC | 0.00% | Add +3.3% | 1,098,166 | $10.7M |
| Federated Hermes, Inc. | 0.02% | Add +8.8% | 1,059,849 | $10.3M |
| Jacobs Levy Equity Management, Inc. | 0.04% | Reduce -0.6% | 972,017 | $9.4M |
| Goldman Sachs Group Inc. | 0.00% | Reduce -12.4% | 818,885 | $8.0M |
| Dimensional Fund Advisors LP | 0.00% | Add +0.9% | 782,603 | $7.6M |
| Nuveen, LLC | 0.00% | Add +0.0% | 759,368 | $7.4M |
| Qube Research & Technologies Ltd | 0.01% | Add +50.8% | 614,603 | $6.0M |
| Renaissance Technologies | 0.01% | Add +39.5% | 607,515 | $5.9M |
| Mariner, LLC | 0.01% | Reduce -2.6% | 563,082 | $5.5M |
| Monimus Capital Management, LP | 1.31% | Add +91.1% | 485,617 | $4.7M |
| Vanguard Capital Management LLC | 0.00% | — | 484,126 | $4.7M |
| Rangeley Capital, LLC | 4.74% | Reduce -14.3% | 449,460 | $4.4M |
| Birchview Capital, LP | 2.48% | Add +1.8% | 449,019 | $4.4M |
| Armistice Capital, LLC | 0.14% | Reduce -70.7% | 439,411 | $4.3M |
| Citadel Advisors | 0.00% | Reduce -52.3% | 435,574 | $4.2M |
| BNP Paribas Financial Markets | 0.00% | Add +0.1% | 424,596 | $4.1M |
| Point72 Asset Management | 0.01% | Reduce -53.5% | 399,830 | $3.9M |
| Bank of America Corp. | 0.00% | Reduce -7.9% | 393,632 | $3.8M |
| Man Group plc | 0.01% | Add +41.6% | 381,574 | $3.7M |
| Northern Trust Corp. | 0.00% | Add +1.7% | 369,542 | $3.6M |
| Charles Schwab Investment Management Inc. | 0.00% | Reduce -0.2% | 356,665 | $3.5M |
| UBS Group AG | 0.00% | Reduce -22.9% | 328,491 | $3.2M |
| Deeter Investments LLP | 0.51% | New | 300,000 | $2.9M |
| Walleye Capital LLC | 0.02% | Add +77.6% | 277,168 | $2.7M |
| Penbrook Management LLC | 2.00% | New | 271,720 | $2.6M |
| Vanguard Fiduciary Trust Co. | 0.00% | — | 254,573 | $2.5M |
| Squarepoint Ops LLC | 0.00% | Add +5.9% | 230,920 | $2.2M |
| Focused Wealth Management, Inc | 0.21% | Add +93.0% | 207,403 | $2.0M |
| AQR Capital Management | 0.00% | Add +9.2% | 204,016 | $2.0M |
| Connor, Clark & Lunn Investment Management Ltd. | 0.00% | Add +24.4% | 156,551 | $1.5M |
| Quantinno Capital Management LP | 0.00% | Add +39.3% | 144,299 | $1.4M |
| Campbell & CO Investment Adviser LLC | 0.08% | Add +51.4% | 142,587 | $1.4M |
| Bank of New York Mellon Corp | 0.00% | Add +2.7% | 136,322 | $1.3M |
| Massachusetts Financial Services Co. | 0.00% | Add +187.3% | 132,051 | $1.3M |
| Jump Financial, LLC | 0.02% | Reduce -50.0% | 118,936 | $1.2M |
| Jane Street Group, LLC | 0.00% | Reduce -74.8% | 107,926 | $1.0M |
| Y-Intercept (Hong Kong) Ltd | 0.02% | Add +0.3% | 100,805 | $980K |
| Russell Investments Group, Ltd. | 0.00% | Add +1.3% | 100,627 | $978K |
| T. Rowe Price Associates Inc. | 0.00% | Add +17.3% | 95,649 | $930K |
| XTX Topco Ltd | 0.02% | Add +68.2% | 92,326 | $897K |
| Ameriprise Financial Inc. | 0.00% | Reduce -15.4% | 89,212 | $867K |
| Hennion & Walsh Asset Management, Inc. | 0.03% | Reduce -3.0% | 88,544 | $861K |
| American Century Companies Inc. | 0.00% | Add +1.1% | 79,631 | $774K |
| Assenagon Asset Management S.A. | 0.00% | No change | 76,769 | $746K |
| DCF Advisers, LLC | 0.27% | Reduce -62.6% | 73,247 | $712K |
| Creative Planning | 0.00% | Add +17.8% | 72,986 | $709K |
| Duncan Williams Asset Management, LLC | 0.19% | No change | 70,281 | $683K |
| Martingale Asset Management L P | 0.02% | Add +8.9% | 69,101 | $672K |
| Alliancebernstein L.P. | 0.00% | No change | 69,607 | $665K |
| Susquehanna Portfolio Strategies, LLC | 0.01% | Add +15.3% | 67,870 | $660K |
| HSBC Holdings PLC | 0.00% | Add +134.6% | 65,070 | $632K |
| Pinnacle Associates Ltd. | 0.01% | Reduce -3.3% | 60,662 | $590K |
| Rhumbline Advisers | 0.00% | Reduce -2.0% | 55,367 | $538K |
| Jackson Creek Investment Advisors LLC | 0.15% | New | 54,089 | $526K |
| Rafferty Asset Management, LLC | 0.00% | Reduce -35.5% | 53,266 | $518K |
| Quinn Opportunity Partners LLC | 0.03% | No change | 50,000 | $486K |
| Edgewood Management LLC | 0.00% | Add +107.8% | 50,000 | $486K |
| Invesco Ltd. | 0.00% | Add +87.2% | 49,808 | $484K |
| Marshall Wace, LLP | 0.00% | Reduce -18.6% | 44,574 | $433K |
| Seven Fleet Capital Management LP | 0.13% | No change | 43,300 | $421K |
| Public Employees Retirement System of Ohio | 0.00% | No change | 42,158 | $410K |
| Barclays PLC | 0.00% | Reduce -77.8% | 40,862 | $397K |
| Deutsche Bank AG | 0.00% | Add +12.8% | 40,018 | $389K |
| WINTON GROUP Ltd | 0.01% | New | 34,700 | $337K |
| Fox Run Management, L.L.C. | 0.06% | Add +248.9% | 35,052 | $324K |
| Covestor Ltd | 0.22% | Add +49.9% | 32,657 | $317K |
| Gsa Capital Partners LLP | 0.02% | Add +23.3% | 32,499 | $316K |
| Cornerstone Investment Partners, LLC | 0.01% | New | 30,687 | $298K |
| Great Lakes Advisors, LLC | 0.00% | Add +124.4% | 29,593 | $288K |
| RBF Capital, LLC | 0.01% | No change | 29,200 | $284K |
| PNC Financial Services Group, Inc. | 0.00% | Add +0.9% | 28,386 | $276K |
| Wells Fargo & Company | 0.00% | Reduce -54.5% | 27,337 | $266K |
| Virtus Investment Advisers, LLC | 0.07% | Add +2.5% | 26,320 | $256K |
| Purkiss Capital Advisors LLC | 0.11% | No change | 25,086 | $244K |
| JPMorgan Chase & Co. | 0.00% | Reduce -84.7% | 25,967 | $240K |
| Trexquant Investment LP | 0.00% | Add +26.6% | 24,543 | $239K |
| Tudor Investment Corporation | 0.00% | Reduce -7.6% | 24,471 | $238K |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | 0.00% | Reduce -2.4% | 24,639 | $238K |
| Los Angeles Capital Management LLC | 0.00% | Reduce -74.4% | 24,419 | $237K |
| Profund Advisors LLC | 0.01% | Reduce -21.6% | 24,005 | $233K |
| Mogy Joel R Investment Counsel Inc. | 0.01% | No change | 20,750 | $202K |
| MetLife Investment Management, LLC | 0.00% | Reduce -23.5% | 19,516 | $190K |
| Foundation Wealth Management, LLC | 0.13% | New | 19,236 | $187K |
| Jones Financial Companies LLLP | 0.00% | Add +22.1% | 19,409 | $180K |
| Vanguard Global Advisers, LLC | 0.00% | — | 18,249 | $177K |
| Susquehanna International Group, LLP | 0.00% | Add +11.4% | 17,792 | $173K |
| Sei Investments Co. | 0.00% | New | 17,248 | $168K |
| Chicago Partners Investment Group LLC | 0.00% | Add +0.9% | 15,365 | $165K |
| Ballentine Partners, LLC | 0.00% | Reduce -7.1% | 16,793 | $163K |
"% of holder's portfolio" is PRTA's weight in each manager's 13F, not the share of Prothena Corp. PLC the manager owns.