PROTHENA CORP PLC (PRTA)
Institutional ownership reported to the SEC as of Q2 2026, across 31 quarters.
187
Reporting holders
$482.2M
Reported value
93.2%
Of shares outstanding
2.9%
Held as options
+9
Holder change
Institutions report 47,823,606 shares against 51,336,974 outstanding. Shares only - option lines are excluded, which is why this can be compared with the company at all. The count comes from the cover page of the company's own most recent report, so it is dated when that was filed rather than at quarter end. A figure this high can overstate: where an adviser and a sub-adviser both report the same shares, both are counted.
Options share is the part of reported value carried in derivative lines rather than shares. A high figure means institutions are expressing a view on this security without owning much of it.
Holders
| Filer | Value | Shares | Their book | Held | Change |
|---|---|---|---|---|---|
| FMR LLC | $70.5M | 7,199,218 | 0.00% | 31q | -4.7%-$3.4M |
| Rubric Capital Management LP | $49.0M | 5,000,000 | 0.45% | 4q | HELD |
| BlackRock, Inc. | $47.7M | 4,867,955 | 0.00% | 8q | +4.8%+$2.2M |
| Palo Alto Investors LP | $33.6M | 3,429,465 | 1.55% | 31q | +183.8%+$21.7M |
| STATE STREET CORP | $23.4M | 2,393,424 | 0.00% | 31q | +23.5%+$4.5M |
| VANGUARD PORTFOLIO MANAGEMENT LLC | $16.2M | 1,651,293 | 0.00% | 2q | +14.2%+$2.0M |
| D. E. Shaw & Co., Inc. | $15.8M | 1,611,457 | 0.01% | 6q | -8.6%-$1.5M |
| ADAR1 Capital Management, LLC | $15.2M | 1,554,535 | 0.70% | 5q | -1.7%-$263.4K |
| TWO SIGMA INVESTMENTS, LP | $12.4M | 1,264,987 | 0.01% | 9q | +4.9%+$577.7K |
| GEODE CAPITAL MANAGEMENT, LLC | $11.0M | 1,125,877 | 0.00% | 31q | +2.5%+$271.4K |
| FEDERATED HERMES, INC. | $10.6M | 1,084,401 | 0.02% | 9q | +2.3%+$240.4K |
| MORGAN STANLEY | $9.7M | 995,348 | 0.00% | 35q | -19.1%-$2.3M |
| GOLDMAN SACHS GROUP INC | $9.6M | 979,730 | 0.00% | 31q | +19.6%+$1.6M |
| JACOBS LEVY EQUITY MANAGEMENT, INC | $9.5M | 965,988 | 0.03% | 6q | -0.6%-$59.0K |
| DIMENSIONAL FUND ADVISORS LP | $8.9M | 905,651 | 0.00% | 31q | +15.7%+$1.2M |
| Qube Research & Technologies Ltd | $7.7M | 791,169 | 0.01% | 5q | +28.7%+$1.7M |
| RENAISSANCE TECHNOLOGIES LLC | $6.8M | 697,615 | 0.01% | 28q | +14.8%+$882.1K |
| Man Group plc | $6.6M | 678,116 | 0.01% | 17q | +77.7%+$2.9M |
| Mariner, LLC | $6.1M | 625,095 | 0.01% | 19q | +11.0%+$607.1K |
| CITADEL ADVISORS LLC | $5.9M | 338,810 | 0.00% | 31q | -22.2%-$1.7M |
| Nuveen, LLC | $5.5M | 557,157 | 0.00% | 6q | -26.6%-$2.0M |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | $4.8M | options only | 0.00% | 31q | OPTIONS |
| VANGUARD CAPITAL MANAGEMENT LLC | $4.7M | 479,945 | 0.00% | 2q | -0.9%-$40.9K |
| NORTHERN TRUST CORP | $4.5M | 457,124 | 0.00% | 31q | +23.7%+$857.4K |
| Birchview Capital, LP | $4.4M | 449,019 | 2.06% | 21q | HELD |
| Rangeley Capital, LLC | $4.1M | 417,270 | 3.73% | 5q | -7.2%-$315.1K |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | $3.5M | 355,896 | 0.00% | 31q | HELD |
| Sixth Street Partners Management Company, L.P. | $3.5M | 355,896 | 0.00% | new | NEW |
| MONIMUS CAPITAL MANAGEMENT, LP | $3.2M | 329,052 | 0.75% | 5q | -32.2%-$1.5M |
| BNP PARIBAS FINANCIAL MARKETS | $3.1M | 315,803 | 0.00% | 31q | -25.6%-$1.1M |
| AQR CAPITAL MANAGEMENT LLC | $3.0M | 302,572 | 0.00% | 4q | +48.3%+$964.9K |
| Penbrook Management LLC | $2.7M | 271,720 | 1.70% | 2q | HELD |
| VANGUARD FIDUCIARY TRUST CO | $2.5M | 259,064 | 0.00% | 2q | +1.8%+$44.0K |
| UBS Group AG | $2.4M | 241,425 | 0.00% | 31q | -26.5%-$852.4K |
| MACKENZIE FINANCIAL CORP | $2.3M | 239,899 | 0.00% | new | NEW |
| Coppell Advisory Solutions LLC | $2.3M | 12 | 0.19% | new | NEW |
| GROUP ONE TRADING LLC | $2.2M | options only | 0.00% | 16q | OPTIONS |
| Squarepoint Ops LLC | $2.2M | 223,971 | 0.00% | 5q | -3.0%-$68.0K |
| BANK OF AMERICA CORP /DE/ | $2.0M | 208,246 | 0.00% | 31q | -47.1%-$1.8M |
| Focused Wealth Management, Inc | $2.0M | 207,445 | 0.18% | 7q | HELD |
| Connor, Clark & Lunn Investment Management Ltd. | $1.9M | 191,693 | 0.00% | 3q | +22.4%+$344.0K |
| MARSHALL WACE, LLP | $1.9M | 190,834 | 0.00% | 3q | +328.1%+$1.4M |
| SIMPLEX TRADING, LLC | $1.6M | options only | 0.00% | 23q | OPTIONS |
| Quantinno Capital Management LP | $1.6M | 158,331 | 0.00% | 5q | +9.7%+$137.4K |
| JANE STREET GROUP, LLC | $1.5M | options only | 0.00% | 14q | OPTIONS |
| MILLENNIUM MANAGEMENT LLC | $1.5M | options only | 0.00% | 31q | OPTIONS |
| DIADEMA PARTNERS LP | $1.5M | 149,482 | 0.18% | new | NEW |
| Bank of New York Mellon Corp | $1.3M | 133,906 | 0.00% | 31q | -1.8%-$23.7K |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ | $1.2M | 126,990 | 0.00% | 7q | -3.8%-$49.5K |
| Assenagon Asset Management S.A. | $1.2M | 125,570 | 0.00% | 4q | +63.6%+$477.8K |
| Russell Investments Group, Ltd. | $1.2M | 121,901 | 0.00% | 11q | +21.1%+$208.3K |
| Hennion & Walsh Asset Management, Inc. | $888.9K | 90,795 | 0.03% | 7q | +2.5%+$22.0K |
| AMERICAN CENTURY COMPANIES INC | $887.4K | 90,644 | 0.00% | 8q | +13.8%+$107.8K |
| AMERIPRISE FINANCIAL INC | $853.8K | 87,215 | 0.00% | 5q | -51.1%-$892.9K |
| XTX Topco Ltd | $839.2K | 85,717 | 0.01% | 4q | -7.2%-$64.7K |
| Susquehanna Portfolio Strategies, LLC | $809.7K | 82,710 | 0.01% | 5q | +21.9%+$145.3K |
| ExodusPoint Capital Management, LP | $803.0K | 82,023 | 0.01% | 6q | +634.2%+$693.6K |
| MARTINGALE ASSET MANAGEMENT L P | $771.5K | 78,800 | 0.02% | 3q | +14.0%+$95.0K |
| Trexquant Investment LP | $751.2K | 76,731 | 0.00% | 5q | +212.6%+$510.9K |
| DCF Advisers, LLC | $717.1K | 73,247 | 0.13% | 22q | HELD |
| Invesco Ltd. | $699.8K | 71,479 | 0.00% | 31q | +43.5%+$212.2K |
| STATE OF WISCONSIN INVESTMENT BOARD | $688.5K | 70,326 | 0.00% | new | NEW |
| Duncan Williams Asset Management, LLC | $688.1K | 70,281 | 0.16% | 8q | HELD |
| ALLIANCEBERNSTEIN L.P. | $672.8K | 69,217 | 0.00% | 31q | -0.6%-$3.8K |
| Campbell & CO Investment Adviser LLC | $669.1K | 68,345 | 0.04% | 3q | -52.1%-$726.8K |
| Creative Planning | $613.0K | 62,620 | 0.00% | 8q | -14.2%-$101.5K |
| PINNACLE ASSOCIATES LTD | $567.0K | 57,918 | 0.01% | 31q | -4.5%-$26.9K |
| CITIGROUP INC | $566.1K | 57,827 | 0.00% | 31q | +609.5%+$486.3K |
| RHUMBLINE ADVISERS | $547.2K | 55,896 | 0.00% | 31q | +1.0%+$5.2K |
| Schonfeld Strategic Advisors LLC | $492.9K | 50,350 | 0.00% | 2q | +306.1%+$371.5K |
| HSBC HOLDINGS PLC | $492.2K | 49,569 | 0.00% | 8q | -23.8%-$153.9K |
| EDGEWOOD MANAGEMENT LLC | $489.5K | 50,000 | 0.01% | 23q | HELD |
| Quinn Opportunity Partners LLC | $489.5K | 50,000 | 0.02% | 5q | HELD |
| WELLS FARGO & COMPANY/MN | $484.8K | 49,520 | 0.00% | 31q | -9.4%-$50.5K |
| Seven Fleet Capital Management LP | $423.9K | 43,300 | 0.07% | 3q | HELD |
| DEUTSCHE BANK AG\ | $423.6K | 43,270 | 0.00% | 34q | +8.1%+$31.8K |
| PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO | $412.7K | 42,158 | 0.00% | 5q | HELD |
| Engineers Gate Manager LP | $404.0K | 41,270 | 0.01% | new | NEW |
| Rafferty Asset Management, LLC | $395.5K | 40,397 | 0.00% | 3q | -24.2%-$126.0K |
| Virtus Investment Advisers, LLC | $388.3K | 39,660 | 0.09% | 6q | +50.7%+$130.6K |
| SHELTON CAPITAL MANAGEMENT | $386.4K | 39,472 | 0.01% | new | NEW |
| Persistent Asset Partners Ltd | $373.0K | 38,100 | 0.11% | new | NEW |
| BARCLAYS PLC | $368.3K | 37,623 | 0.00% | 31q | -7.9%-$31.7K |
| SEI INVESTMENTS CO | $302.3K | 30,877 | 0.00% | 2q | +79.0%+$133.4K |
| WINTON GROUP Ltd | $298.6K | 30,500 | 0.01% | 2q | -12.1%-$41.1K |
| RBF Capital, LLC | $285.9K | 29,200 | 0.01% | 27q | HELD |
| GREAT LAKES ADVISORS, LLC | $281.3K | 28,733 | 0.00% | 4q | -2.9%-$8.4K |
| PNC Financial Services Group, Inc. | $277.9K | 28,386 | 0.00% | 25q | HELD |
| JPMORGAN CHASE & CO | $265.4K | 26,620 | 0.00% | 31q | +2.5%+$6.5K |
| MetLife Investment Management, LLC | $253.5K | 25,890 | 0.00% | 32q | +32.7%+$62.4K |
| Aquatic Capital Management LLC | $248.9K | 25,419 | 0.01% | new | NEW |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | $247.3K | 25,174 | 0.00% | 9q | +2.2%+$5.3K |
| Purkiss Capital Advisors LLC | $245.6K | 25,086 | 0.09% | 7q | HELD |
| TUDOR INVESTMENT CORP ET AL | $239.3K | 24,445 | 0.00% | 5q | HELD |
| CANADA PENSION PLAN INVESTMENT BOARD | $235.0K | 24,000 | 0.00% | new | NEW |
| MERCER GLOBAL ADVISORS INC /ADV | $224.3K | 22,908 | 0.00% | 2q | +75.0%+$96.1K |
| ENVESTNET ASSET MANAGEMENT INC | $224.3K | 22,908 | 0.00% | new | NEW |
| FORTRESS FINANCIAL GROUP, LLC | $219.8K | 6 | 0.06% | new | NEW |
| MOGY JOEL R INVESTMENT COUNSEL INC | $203.1K | 20,750 | 0.01% | 5q | HELD |
| PROFUND ADVISORS LLC | $201.4K | 20,570 | 0.01% | 3q | -14.3%-$33.6K |
Five percent filings
Anyone crossing 5% of a company must say so within days - far sooner than the next quarterly holdings report. A 13D declares an intent to influence the company; a 13G is the passive version. See all activist filings →
| Filed | Form | Filer | % of class |
|---|---|---|---|
| 2026-08-19 | 13G/A | Fennell Todd W. INDIVIDUAL | 10.2% |
| 2026-08-14 | 13G/A | Fennell Todd W. INDIVIDUAL | 9.8% |
| 2026-08-06 | 13G/A | FMR LLCwith 1 co-filers | 13.8% |
| 2026-07-29 | 13G/A | BlackRock, Inc. | 6.9% |
Quarter by quarter
Coverage begins with the quarter ending 2018-12-31. Earlier filings exist only as occasional late amendments, too sparse to describe a market, so they are not shown.
| Quarter | Holders | Value | Shares | New | Added | Trimmed | Options |
|---|---|---|---|---|---|---|---|
| Q2 2026 | 187 | $482.2M | 47,823,606 | 26 | 53 | 54 | 2.9% |
| Q1 2026 | 178 | $446.5M | 45,317,553 | 24 | 61 | 49 | 1.4% |
| Q4 2025 | 172 | $450.7M | 45,648,066 | 20 | 60 | 51 | 3.3% |
| Q3 2025 | 175 | $427.8M | 42,293,114 | 29 | 50 | 57 | 4.5% |
| Q2 2025 | 178 | $255.3M | 40,301,046 | 49 | 47 | 39 | 4.3% |
| Q1 2025 | 153 | $606.3M | 48,634,904 | 13 | 35 | 54 | 0.7% |
| Q4 2024 | 164 | $704.7M | 50,003,737 | 26 | 54 | 36 | 1.7% |
| Q3 2024 | 150 | $799.3M | 47,407,811 | 19 | 44 | 42 | 0.6% |
| Q2 2024 | 148 | $973.4M | 47,047,774 | 24 | 51 | 39 | 0.4% |
| Q1 2024 | 151 | $1.3B | 50,573,348 | 20 | 50 | 54 | 0.7% |
| Q4 2023 | 173 | $1.9B | 49,400,277 | 29 | 63 | 39 | 7.1% |
| Q3 2023 | 172 | $2.3B | 47,937,076 | 22 | 66 | 46 | 1.2% |
| Q2 2023 | 179 | $3.2B | 46,731,310 | 30 | 66 | 48 | 1.5% |
| Q1 2023 | 158 | $2.6B | 52,454,117 | 20 | 54 | 46 | 0.4% |
| Q4 2022 | 170 | $2.5B | 40,799,998 | 41 | 60 | 40 | 1.2% |
| Q3 2022 | 181 | $2.8B | 44,642,192 | 45 | 49 | 49 | 3.2% |
| Q2 2022 | 153 | $1.2B | 44,616,989 | 16 | 41 | 47 | 1.4% |
| Q1 2022 | 162 | $1.6B | 44,141,093 | 14 | 52 | 52 | 1.1% |
| Q4 2021 | 186 | $2.2B | 43,079,981 | 30 | 70 | 35 | 1.1% |
| Q3 2021 | 185 | $2.9B | 40,926,982 | 47 | 55 | 48 | 1.0% |
| Q2 2021 | 155 | $2.1B | 40,602,196 | 36 | 48 | 40 | 1.2% |
| Q1 2021 | 139 | $1.0B | 39,992,598 | 23 | 34 | 48 | 2.1% |
| Q4 2020 | 129 | $425.2M | 34,821,535 | 24 | 24 | 50 | 1.6% |
| Q3 2020 | 127 | $365.4M | 36,213,590 | 17 | 31 | 50 | 1.0% |
| Q2 2020 | 124 | $398.3M | 37,861,523 | 19 | 34 | 43 | 0.6% |
| Q1 2020 | 114 | $402.9M | 37,354,263 | 9 | 35 | 37 | 0.8% |
| Q4 2019 | 127 | $603.9M | 37,617,514 | 24 | 35 | 36 | 1.4% |
| Q3 2019 | 112 | $296.5M | 37,667,043 | 11 | 32 | 41 | 0.4% |
| Q2 2019 | 118 | $413.7M | 38,986,980 | 22 | 42 | 26 | 0.4% |
| Q1 2019 | 118 | $483.9M | 39,568,584 | 26 | 36 | 27 | 0.8% |
| Q4 2018 | 97 | $434.8M | 40,684,783 | 3 | 1 | 2 | 3.6% |