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Prothena (PRTA) Institutional Ownership

Prothena logo
$9.59 -0.17 (-1.74%)
Closing price 05/18/2026 04:00 PM Eastern
Extended Trading
$9.85 +0.26 (+2.66%)
As of 05/18/2026 04:10 PM Eastern
Extended trading is trading that happens on electronic markets outside of regular trading hours. This is a fair market value extended hours price provided by Massive. Learn more.
Compare

Institutional Ownership Changes (13F Filings) for Prothena (NASDAQ:PRTA)

Current
Institutional Ownership
Percentage
97.08%
Number of
Institutional Buyers
(last 12 months)
99
Total
Institutional Inflows
(last 12 months)
$169.05M
Number of
Institutional Sellers
(last 12 months)
54
Total
Institutional Outflows
(last 12 months)
$52.08M
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Skip Chart & View Institutional Buying and Selling Data

PRTA Institutional Buying and Selling by Quarter

Prothena Major Shareholders & Ownership History

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Reporting DateMajor Shareholder NameShares HeldMarket Value% of PortfolioQuarterly Change in SharesOwnership in CompanyDetails
5/18/2026ADAR1 Capital Management LLC1,581,443$15.37M0.9%+8.5%3.021%
5/18/2026 Royal Bank of Canada3,171$30K0.0%-28.4%0.006%
5/18/2026 Rubric Capital Management LP5,000,000$48.60M0.5%+36.0%9.551%
5/16/2026 The Manufacturers Life Insurance Company 12,184$118K0.0%-11.0%0.023%
5/16/2026 Quantinno Capital Management LP144,299$1.40M0.0%+39.3%0.276%
5/15/2026 Rangeley Capital LLC449,460$4.37M4.0%-14.3%0.859%
5/14/2026 Renaissance Technologies LLC607,515$5.91M0.0%+39.5%1.160%
5/14/2026 Sei Investments Co.17,248$168K0.0%N/A0.033%
5/7/2026 Dimensional Fund Advisors LP782,603$7.61M0.0%+1.0%1.454%
5/5/2026 Bank of New York Mellon Corp136,322$1.33M0.0%+2.7%0.253%
4/30/2026 Hsbc Holdings PLC65,070$632K0.0%+134.6%0.121%
4/25/2026 Strs Ohio14,700$143K0.0%-16.5%0.027%
4/24/2026 CHICAGO TRUST Co NA15,057$146K0.0%N/A0.028%
4/21/2026 Penbrook Management LLC271,720$2.64M2.0%N/A0.505%
4/20/2026 Focused Wealth Management Inc207,403$2.02M0.2%+93.0%0.385%
4/16/2026 SG Americas Securities LLC13,522$131K0.0%-78.5%0.025%
3/20/2026 Hsbc Holdings PLC27,733$261K0.0%-25.9%0.052%
2/26/2026 Seven Fleet Capital Management LP43,300$414K0.3%N/A0.080%
2/19/2026 Invesco Ltd.26,609$254K0.0%-15.0%0.049%
2/18/2026ADAR1 Capital Management LLC1,457,764$13.92M1.0%-0.8%2.708%
2/18/2026 XTX Topco Ltd54,881$524K0.0%+247.2%0.102%
2/18/2026 Virtus Investment Advisers LLC25,679$245K0.1%+14.4%0.048%
2/18/2026 Susquehanna Portfolio Strategies LLC58,853$562K0.0%+103.1%0.109%
2/18/2026 Polymer Capital Management US LLC23,513$225K0.0%N/A0.044%
2/18/2026 Quadrature Capital Ltd31,090$297K0.0%+14.2%0.058%
2/18/2026 Man Group plc269,513$2.57M0.0%+104.2%0.501%
2/18/2026 Armistice Capital LLC1,500,000$14.33M0.2%-17.8%2.787%
2/17/2026ADAR1 Capital Management LLC1,457,764$13.92M1.0%-0.8%2.708%
2/17/2026 PDT Partners LLC11,334$108K0.0%N/A0.021%
2/17/2026 AQR Capital Management LLC186,785$1.78M0.0%-12.9%0.347%
2/17/2026 Trexquant Investment LP19,384$185K0.0%-93.1%0.036%
2/17/2026 Jump Financial LLC237,828$2.27M0.0%+27.7%0.442%
2/17/2026 Price T Rowe Associates Inc. MD81,515$779K0.0%+3.8%0.151%
2/17/2026 Monimus Capital Management LP254,122$2.43M1.6%-1.5%0.472%
2/17/2026 Diadema Partners LP106,539$1.02M0.2%N/A0.198%
2/17/2026 Russell Investments Group Ltd.99,350$949K0.0%-22.2%0.185%
2/17/2026 Atom Investors LP17,026$163K0.0%-20.1%0.032%
2/17/2026 ExodusPoint Capital Management LP87,990$840K0.0%+190.8%0.163%
2/17/2026 Royal Bank of Canada4,427$42K0.0%-57.1%0.008%
2/17/2026 Graham Capital Management L.P.27,756$265K0.0%-48.0%0.052%
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2/17/2026 Persistent Asset Partners Ltd28,589$273K0.1%N/A0.053%
2/16/2026 Squarepoint Ops LLC218,041$2.08M0.0%+71.6%0.405%
2/16/2026 Mariner LLC577,938$5.52M0.0%-2.2%1.074%
2/16/2026 Entropy Technologies LP16,900$161K0.0%N/A0.031%
2/16/2026 Barclays PLC183,625$1.75M0.0%+87.2%0.341%
2/13/2026 Marshall Wace LLP54,778$523K0.0%N/A0.102%
2/13/2026 Rubric Capital Management LP3,677,331$35.12M0.4%+138.7%6.831%
2/13/2026 Jacobs Levy Equity Management Inc.978,011$9.34M0.0%+11.6%1.817%
2/13/2026 Rafferty Asset Management LLC82,553$788K0.0%N/A0.153%
2/13/2026 Headlands Technologies LLC23,352$223K0.0%N/A0.043%
2/13/2026 Birchview Capital LP441,019$4.21M2.5%-19.7%0.819%
2/13/2026 Charles Schwab Investment Management Inc.357,335$3.41M0.0%+1.9%0.664%
2/13/2026 State Street Corp2,267,802$21.66M0.0%+151.7%4.213%
2/13/2026 Martingale Asset Management L P63,453$606K0.0%N/A0.118%
2/13/2026 Wells Fargo & Company MN60,108$574K0.0%+48.7%0.112%
2/12/2026 DRW Securities LLC11,955$114K0.0%N/A0.022%
2/12/2026 MetLife Investment Management LLC25,501$244K0.0%+31.7%0.047%
2/12/2026 Renaissance Technologies LLC435,515$4.16M0.0%+17.3%0.809%
2/12/2026 Dimensional Fund Advisors LP775,207$7.40M0.0%-3.9%1.440%
2/12/2026 Federated Hermes Inc.974,367$9.31M0.0%+40.6%1.810%
2/12/2026 Campbell & CO Investment Adviser LLC94,155$899K0.0%N/A0.175%
2/12/2026 Nuveen LLC759,107$7.25M0.0%+13.6%1.410%
2/11/2026 DCF Advisers LLC195,747$1.87M0.5%-2.5%0.364%
2/11/2026 Deutsche Bank AG35,482$339K0.0%+5.1%0.066%
2/11/2026 Fox Run Management L.L.C.10,045$96K0.0%-77.3%0.019%
2/11/2026 Franklin Resources Inc.47,251$451K0.0%-22.8%0.088%
2/11/2026 Los Angeles Capital Management LLC95,406$1M0.0%-20.1%0.177%
2/10/2026 Goldman Sachs Group Inc.935,333$8.93M0.0%+164.8%1.738%
2/10/2026 Intech Investment Management LLC20,601$197K0.0%+6.3%0.038%
2/9/2026 Geode Capital Management LLC1,063,069$10.15M0.0%+4.3%1.975%
2/6/2026 Covestor Ltd21,793$208K0.1%-30.7%0.040%
2/6/2026 PNC Financial Services Group Inc.28,128$269K0.0%+55.1%0.052%
2/6/2026 ProShare Advisors LLC10,425$100K0.0%N/A0.019%
2/5/2026 Duncan Williams Asset Management LLC70,281$625K0.2%-20.4%0.131%
2/5/2026 Pinnacle Associates Ltd.62,724$599K0.0%-12.0%0.117%
2/2/2026 Strs Ohio17,600$168K0.0%-38.9%0.033%
1/29/2026 UBS Group AG426,360$4.07M0.0%+6.4%0.792%
1/29/2026 Focused Wealth Management Inc107,479$1.03M0.1%+88.1%0.200%
1/22/2026 Massachusetts Financial Services Co. MA45,970$439K0.0%-3.2%0.085%
1/14/2026 Hennion & Walsh Asset Management Inc.91,284$872K0.0%+7.9%0.170%
1/9/2026 SG Americas Securities LLC63,018$602K0.0%+11.1%0.117%
1/9/2026 Assenagon Asset Management S.A.76,769$733K0.0%-14.4%0.143%
1/1/2026 JPMorgan Chase & Co.735,765$7.18M0.0%+479.6%1.367%
11/17/2025 Jacobs Levy Equity Management Inc.876,528$8.56M0.0%+26.5%1.628%
11/17/2025 Armistice Capital LLC1,824,000$17.80M0.3%-18.4%3.388%
11/17/2025 Proficio Capital Partners LLC30,136$294K0.0%N/A0.056%
11/17/2025 Qube Research & Technologies Ltd254,245$2.48M0.0%-38.7%0.472%
11/17/2025 Palo Alto Investors LP1,324,028$12.92M2.4%+3.9%2.460%
11/17/2025 Mariner LLC590,897$5.77M0.0%+52.8%1.098%
11/17/2025 Millennium Management LLC621,099$6.06M0.0%+264.1%1.154%
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11/17/2025 MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd.18,834$184K0.0%-11.2%0.035%
11/17/2025 Jain Global LLC11,780$115K0.0%-35.5%0.022%
11/17/2025Bank of America Corp DE277,096$2.70M0.0%+31.4%0.515%
11/17/2025 Algert Global LLC445,811$4.35M0.1%+825.9%0.828%
11/17/2025 Alliancebernstein L.P.69,607$679K0.0%-20.5%0.129%
11/17/2025 Ameriprise Financial Inc.105,536$1.03M0.0%-30.4%0.196%
11/14/2025 Creative Planning64,140$626K0.0%+26.8%0.119%
11/14/2025 Raymond James Financial Inc.22,032$215K0.0%+63.2%0.041%
11/14/2025Sandia Investment Management LP29,950$292K0.9%N/A0.056%
11/14/2025 Rubric Capital Management LP1,540,373$15.03M0.2%N/A2.862%


PRTA Institutional Ownership - Frequently Asked Questions

During the previous two years, 161 institutional investors and hedge funds held shares of Prothena. The most heavily invested institutionals were FMR LLC ($111.79M), Wellington Management Group LLP ($64.34M), Rubric Capital Management LP ($48.60M), State Street Corp ($21.66M), Vanguard Group Inc. ($20.01M), Siren L.L.C. ($15.88M), and ADAR1 Capital Management LLC ($15.37M).Learn more on Prothena's institutional investors.

97.08% of Prothena's stock is owned by institutional investors. Learn more on PRTA's institutional investor holdings.

Of the 134 institutional investors that purchased Prothena's stock in the last 24 months, the following investors and hedge funds have bought the highest volume of shares: Rubric Capital Management LP ($5M), Wellington Management Group LLP ($2.51M), JPMorgan Chase & Co. ($1.40M), State Street Corp ($1.37M), Federated Hermes Inc. ($1.30M), Acadian Asset Management LLC ($1.02M), and Rangeley Capital LLC ($715.37K).

Institutional investors have bought a total of 19,355,206 shares in the last 24 months. This purchase volume represents approximately $169.05M in transactions.

Of the 54 institutional investors that sold Prothena's stock in the last 24 months, the following investors and hedge funds have sold the highest volume of shares: ADAR1 Capital Management LLC ($1.93M), Armistice Capital LLC ($736K), Federated Hermes Inc. ($488.27K), Trexquant Investment LP ($259.60K), Prosight Management LP ($247.80K), JPMorgan Chase & Co. ($245.01K), and Dimensional Fund Advisors LP ($187.13K).

Institutional investors have sold a total of 5,607,783 shares in the last 24 months. This volume of shares sold represents approximately $52.08M in transactions.


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This page (NASDAQ:PRTA) was last updated on 5/19/2026 by MarketBeat.com Staff.
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