Go Pro
→ Trump Takes Emergency Action - Plus Elon Musk's New Venture (From Altimetry) (Ad)tc pixel Free PRTA Stock Alerts

Prothena (PRTA) Institutional Ownership

Prothena logo
$8.76 +0.18 (+2.10%)
Closing price 08/7/2026 04:00 PM Eastern
Extended Trading
$9.13 +0.37 (+4.27%)
As of 08/7/2026 07:42 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)
88
Total
Institutional Inflows
(last 12 months)
$158.87M
Number of
Institutional Sellers
(last 12 months)
51
Total
Institutional Outflows
(last 12 months)
$50.82M
Get PRTA Insider Trade Alerts

Want to know when executives and insiders are buying or selling Prothena stock? Sign up for InsiderTrades.com's daily newsletter to get the latest insider transactions delivered to your inbox daily.

Subscribe Now
SMS is currently available in Australia, Belgium, Canada, France, Germany, Ireland, Italy, New Zealand, the Netherlands, Singapore, South Africa, Spain, Switzerland, the United Kingdom, and the United States. By entering your phone number and clicking the sign-up button, you agree to receive periodic text messages from MarketBeat at the phone number you submitted, including texts that may be sent using an automatic telephone dialing system. Message and data rates may apply. Message frequency will vary. Messages will consist of stock alerts, news stories, and partner advertisements/offers. Consent is not a condition of the purchase of any goods or services. Text HELP for help/customer support. Unsubscribe at any time by replying "STOP" to any text message that you receive from MarketBeat or by visiting our mailing preferences page. Read our full terms of service and privacy policy.
Skip Chart & View Institutional Buying and Selling Data

PRTA Institutional Buying and Selling by Quarter

Prothena Major Shareholders & Ownership History

Export
Reporting DateMajor Shareholder NameShares HeldMarket Value% of PortfolioQuarterly Change in SharesOwnership in CompanyDetails
7/9/2026 Hennion & Walsh Asset Management Inc.90,795$889K0.0%+2.5%0.173%
7/8/2026 Assenagon Asset Management S.A.62,785$615K0.0%-18.2%0.120%
5/19/2026Bank of America Corp DE393,632$3.83M0.0%-7.9%0.752%
5/18/2026ADAR1 Capital Management LLC1,581,443$15.37M0.9%+8.5%3.021%
5/18/2026Royal Bank of Canada3,171$30K0.0%-28.4%0.006%
5/18/2026Rubric Capital Management LP5,000,000$48.60M0.5%+36.0%9.551%
5/16/2026The Manufacturers Life Insurance Company 12,184$118K0.0%-11.0%0.023%
5/16/2026Quantinno Capital Management LP144,299$1.40M0.0%+39.3%0.276%
5/15/2026Rangeley Capital LLC449,460$4.37M4.0%-14.3%0.859%
5/14/2026Renaissance Technologies LLC607,515$5.91M0.0%+39.5%1.160%
5/14/2026Sei Investments Co.17,248$168K0.0%N/A0.033%
5/7/2026Dimensional 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%
4/30/2026Hsbc 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%
3/20/2026Hsbc Holdings PLC27,733$261K0.0%-25.9%0.052%
2/26/2026Seven Fleet Capital Management LP43,300$414K0.3%N/A0.080%
2/19/2026Invesco Ltd.26,609$254K0.0%-15.0%0.049%
2/18/2026ADAR1 Capital Management LLC1,457,764$13.92M1.0%-0.8%2.708%
2/18/2026XTX Topco Ltd54,881$524K0.0%+247.2%0.102%
2/18/2026Virtus Investment Advisers LLC25,679$245K0.1%+14.4%0.048%
2/18/2026Susquehanna Portfolio Strategies LLC58,853$562K0.0%+103.1%0.109%
2/18/2026Polymer Capital Management US LLC23,513$225K0.0%N/A0.044%
2/18/2026 Quadrature Capital Ltd31,090$297K0.0%+14.2%0.058%
2/18/2026Man Group plc269,513$2.57M0.0%+104.2%0.501%
2/18/2026Armistice 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%
2/17/2026PDT Partners LLC11,334$108K0.0%N/A0.021%
2/17/2026AQR Capital Management LLC186,785$1.78M0.0%-12.9%0.347%
2/17/2026Trexquant Investment LP19,384$185K0.0%-93.1%0.036%
2/17/2026Jump Financial LLC237,828$2.27M0.0%+27.7%0.442%
2/17/2026Price T Rowe Associates Inc. MD81,515$779K0.0%+3.8%0.151%
2/17/2026Monimus Capital Management LP254,122$2.43M1.6%-1.5%0.472%
2/17/2026Diadema Partners LP106,539$1.02M0.2%N/A0.198%
2/17/2026 Russell Investments Group Ltd.99,350$949K0.0%-22.2%0.185%
2/17/2026Atom Investors LP17,026$163K0.0%-20.1%0.032%
They didn't warn anyone in 1971. This time someone is warning you. (Ad)

On August 15, 1971, Nixon interrupted prime-time television and ended the gold standard in 15 minutes - no debate, no vote, one executive order. Gold tripled within three years and climbed 20x over the following decade. Trump holds that same executive authority today, and his advisors are openly saying a reversal is on the table. There are two ways this plays out - both move gold in the same direction. A free briefing breaks down exactly what Nixon did, why Trump is positioned to act, and how to move your 401k into gold before any announcement - tax free.tc pixel

Request the free guide in 30 seconds and get positioned now
2/17/2026ExodusPoint Capital Management LP87,990$840K0.0%+190.8%0.163%
2/17/2026Royal Bank of Canada4,427$42K0.0%-57.1%0.008%
2/17/2026Graham Capital Management L.P.27,756$265K0.0%-48.0%0.052%
2/17/2026 Persistent Asset Partners Ltd28,589$273K0.1%N/A0.053%
2/16/2026Squarepoint Ops LLC218,041$2.08M0.0%+71.6%0.405%
2/16/2026Mariner LLC577,938$5.52M0.0%-2.2%1.074%
2/16/2026Entropy Technologies LP16,900$161K0.0%N/A0.031%
2/16/2026Barclays PLC183,625$1.75M0.0%+87.2%0.341%
2/13/2026Marshall Wace LLP54,778$523K0.0%N/A0.102%
2/13/2026Rubric Capital Management LP3,677,331$35.12M0.4%+138.7%6.831%
2/13/2026Jacobs Levy Equity Management Inc.978,011$9.34M0.0%+11.6%1.817%
2/13/2026Rafferty Asset Management LLC82,553$788K0.0%N/A0.153%
2/13/2026Headlands Technologies LLC23,352$223K0.0%N/A0.043%
2/13/2026Birchview Capital LP441,019$4.21M2.5%-19.7%0.819%
2/13/2026Charles 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%
2/13/2026Martingale Asset Management L P63,453$606K0.0%N/A0.118%
2/13/2026Wells Fargo & Company MN60,108$574K0.0%+48.7%0.112%
2/12/2026DRW Securities LLC11,955$114K0.0%N/A0.022%
2/12/2026MetLife Investment Management LLC25,501$244K0.0%+31.7%0.047%
2/12/2026Renaissance Technologies LLC435,515$4.16M0.0%+17.3%0.809%
2/12/2026Dimensional Fund Advisors LP775,207$7.40M0.0%-3.9%1.440%
2/12/2026Federated 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%
2/12/2026Nuveen LLC759,107$7.25M0.0%+13.6%1.410%
2/11/2026DCF 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%
2/11/2026Franklin Resources Inc.47,251$451K0.0%-22.8%0.088%
2/11/2026Los Angeles Capital Management LLC95,406$1M0.0%-20.1%0.177%
2/10/2026Goldman Sachs Group Inc.935,333$8.93M0.0%+164.8%1.738%
2/10/2026Intech Investment Management LLC20,601$197K0.0%+6.3%0.038%
2/9/2026Geode 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%
2/6/2026ProShare 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%
1/29/2026UBS 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%
1/1/2026JPMorgan Chase & Co.735,765$7.18M0.0%+479.6%1.367%
11/17/2025Jacobs Levy Equity Management Inc.876,528$8.56M0.0%+26.5%1.628%
11/17/2025Armistice Capital LLC1,824,000$17.80M0.3%-18.4%3.388%
11/17/2025Proficio Capital Partners LLC30,136$294K0.0%N/A0.056%
11/17/2025Qube Research & Technologies Ltd254,245$2.48M0.0%-38.7%0.472%
Trump Takes Emergency Action - Plus Elon Musk's New Venture (Ad)

Elon Musk has quietly launched a new venture - one that has nothing to do with rockets, EVs, or Neuralink. Trump has issued emergency support to accelerate the rollout, and it's already live in multiple states. The Financial Times reports Sam Altman is personally calling people to build this for OpenAI. A few little-known companies control the entire supply chain - meaning anyone who wants access must go through them. Their stocks are available to buy right now.tc pixel

See which companies control the supply chain behind this emerging tech
11/17/2025Palo Alto Investors LP1,324,028$12.92M2.4%+3.9%2.460%
11/17/2025Mariner LLC590,897$5.77M0.0%+52.8%1.098%
11/17/2025Millennium Management LLC621,099$6.06M0.0%+264.1%1.154%
11/17/2025MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd.18,834$184K0.0%-11.2%0.035%
11/17/2025Jain Global LLC11,780$115K0.0%-35.5%0.022%
11/17/2025Bank of America Corp DE277,096$2.70M0.0%+31.4%0.515%
11/17/2025Algert Global LLC445,811$4.35M0.1%+825.9%0.828%
11/17/2025Alliancebernstein L.P.69,607$679K0.0%-20.5%0.129%
11/17/2025Ameriprise Financial Inc.105,536$1.03M0.0%-30.4%0.196%
11/14/2025Creative Planning64,140$626K0.0%+26.8%0.119%


PRTA Institutional Ownership - Frequently Asked Questions

During the previous two years, 157 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 131 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. ($1.26M), Acadian Asset Management LLC ($1.02M), and Rangeley Capital LLC ($715.37K).

Institutional investors have bought a total of 17,867,679 shares in the last 24 months. This purchase volume represents approximately $158.87M in transactions.

Of the 51 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 5,419,880 shares in the last 24 months. This volume of shares sold represents approximately $50.82M in transactions.


Related Companies

Institutional ownership data for NASDAQ:PRTA is compiled from quarterly 13F filings submitted to the U.S. Securities and Exchange Commission (SEC), with the most recent received on 7/9/2026. New 13F filings are added each quarter as they're published.
From Our Partners
Louis Navellier: My #1 AI stock for 2026 (name & ticker inside)
Louis Navellier's Stock Grader system helped him flag Nvidia before its 82,000% run and has identified the top...
InvestorPlace | Sponsoredtc pixel
Trump Takes Emergency Action - Plus Elon Musk's New Venture
Elon Musk has quietly launched a new venture - one that has nothing to do with rockets, EVs, or Neuralink. Tru...
Altimetry | Sponsoredtc pixel
Ready to give options a try? Your first trade (Ticker included) -INSIDE
Tired of trying tactic after tactic when it comes to options trades... only to be met with market noise and st...
Base Camp Trading | Sponsoredtc pixel
The $15 Gold Fund That Pays Up to $1,152/Month
Gold is hitting record highs, but most investors are leaving income on the table. A $15 fund is quietly paying...
Investors Alley | Sponsoredtc pixel
Iran War Shock: What I Was Told In That Private Meeting
You’re Being LIED To About The Iran War Forget EVERYTHING you’ve heard about the Iran war. Especially th...
Banyan Hill Publishing | Sponsoredtc pixel
They didn't warn anyone in 1971. This time someone is warning you.
On August 15, 1971, Nixon interrupted prime-time television and ended the gold standard in 15 minutes - no deb...
Reagan Gold Group | Sponsoredtc pixel
Buy this stock today
Marc Chaikin, founder of Chaikin Analytics, is sharing a strategy he calls 'Sell This, Buy That' - a way to mo...
Chaikin Analytics | Sponsoredtc pixel
My top 3 AI picks for the next decade
Alexander Green bought Apple in 1996, recommended Nvidia at a split-adjusted 66 cents in 2004, and picked up A...
The Oxford Club | Sponsoredtc pixel