PRTA on Nasdaq

PROTHENA CORP PUBLIC LTD CO

Pharmaceutical preparations company, listed on Nasdaq (PRTA). Summary from the record

Price unavailable

Last updated Oct 19, 2026.

Overview

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  • TickerPRTA on Nasdaq1
  • IndustryPharmaceutical Preparations1
  • HeadquartersL21
  • Incorporated inIreland2
  • Business address77 Sir John Rogerson'S Quay, Block C, Grand Canal Docklands, Dublin 2, L2 D02 Vk602
  • Filer categoryAccelerated filer2

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Prothena Corporation plc (“Prothena” or the “Company”) is a late-stage clinical biotechnology company with expertise in protein dysregulation with the potential to change the course of devastating neurodegenerative and rare peripheral amyloid diseases.3 From its latest annual report

Financials

From the company’s reports to the SEC. Every number links to the filing it came from.

Key numbers, fiscal 2025

-2216.4%Operating margin4
-2520.6%Net margin4
-92.8%Revenue growth, 20254
-87.0%Return on equity4

What sells

Revenue by product, business segment and region, as the company reports it to the SEC.

Products and services

Collaboration brought in 99% of the revenue PROTHENA CORP PUBLIC LTD CO broke down this way in fiscal 2025.

  1. Collaboration$9.6M499%down 93% from 2024
  2. License$50.0K41%up 0% from 2024
Products and services by year
Products and services202320242025
Collaboration$91.3M$135.1M$9.6M
License$50.0K$50.0K$50.0K

Where the money goes

Where each dollar of revenue went, fiscal 2025

  • Research and development76¢$134.9M
  • Income tax24¢$43.3M

Out of $9.7M in revenue.4 The company lost money this year.

Financial statements

Revenue56784$9.7M in 2025+1090% since 2019
0$100.0M$200.0M$300.0M2019: $814.0K$814.0K20192020: $853.0K$853.0K2020+5%2021: $200.6M$200.6M2021+23414%2022: $53.9M$53.9M2022−73%2023: $91.4M$91.4M2023+70%2024: $135.2M$135.2M2024+48%2025: $9.7M$9.7M2025−93%
Operating income56784-$214.6M in 2025+150% since 2019
-$300.0M-$200.0M-$100.0M0$100.0M2019: -$85.7M-$85.7M20192020: -$112.7M-$112.7M2020+32%2021: $72.0M$72.0M20212022: -$131.6M-$131.6M20222023: -$191.0M-$191.0M2023+45%2024: -$154.6M-$154.6M2024−19%2025: -$214.6M-$214.6M2025+39%
Net income56784-$244.1M in 2025+214% since 2019
-$300.0M-$200.0M-$100.0M0$100.0M2019: -$77.7M-$77.7M20192020: -$111.1M-$111.1M2020+43%2021: $67.0M$67.0M20212022: -$116.9M-$116.9M20222023: -$147.0M-$147.0M2023+26%2024: -$122.3M-$122.3M2024−17%2025: -$244.1M-$244.1M2025+100%

Every line of the income statement as filed: the last 3 fiscal years, latest first.4

Period ending2025-12-312024-12-312023-12-31
Revenues$9.7M$135.2M$91.4M
Research and development$134.9M$222.5M$220.6M
General and administrative$59.4M$67.2M$61.8M
Restructuring costs$30.1M$0$0
Total operating expenses$224.3M$289.7M$282.4M
Loss from operations-$214.6M-$154.6M-$191.0M
Interest income$14.1M$25.8M$31.0M
Other expense, net-$328.0K-$185.0K-$458.0K
Total other income, net$13.8M$25.6M$30.6M
Loss before provision for income taxes-$200.8M-$128.9M-$160.5M
Provision for (benefit from) income taxes$43.3M-$6.6M-$13.5M
Net loss-$244.1M-$122.3M-$147.0M
Basic net loss per ordinary share (in USD per share)-$4.53-$2.27-$2.76
Diluted net loss per ordinary share (in USD per share)-$4.53-$2.27-$2.76
Shares used to compute basic net loss per share (in shares)53.8M shares53.8M shares53.2M shares
Shares used to compute diluted net loss per share (in shares)53.8M shares53.8M shares53.2M shares

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Leadership

Who has led PROTHENA CORP PUBLIC LTD CO, and when. Pick a name to see everywhere that person has worked.

Chief executive

  1. Dale B. Schenk2012–2016
  2. Gene G. Kinney2016–now

President

  1. Dale B. Schenk2012–2016
  2. Gene G. Kinney2016–now

Chief financial officer

  1. Tran Nguyen2013–now

Chief operating officer

  1. Tran Nguyen2018
  2. Brandon S. Smith2021–now
201520202025
Board members and other officers (31)

Former names

  • Prothena Corp plcOct 29, 2012 to May 22, 20202
  • Neotope Corp LtdOct 1, 2012 to Oct 1, 20122

Timeline

  1. Oct 21, 2016New chief executive Gene G. Kinney becomes CEO12
  2. Dec 21, 2012New chief executive Dale B. Schenk becomes CEO13

Filings

429 filings to the SEC since October 2021: 5 annual reports, 15 quarterly reports, 53 major events, 226 insider forms, 52 large holders, 78 other. The latest 20:

  1. Oct 15, 20264 PRIMARY DOCUMENT EDGAR
  2. Oct 9, 20264 PRIMARY DOCUMENT EDGAR
  3. Oct 6, 20264 PRIMARY DOCUMENT EDGAR
  4. Oct 2, 20268-K EDGAR
  5. Sep 30, 20264 PRIMARY DOCUMENT EDGAR
  6. Sep 29, 20264 PRIMARY DOCUMENT EDGAR
  7. Sep 21, 20264 PRIMARY DOCUMENT EDGAR
  8. Sep 3, 20264 PRIMARY DOCUMENT EDGAR
  9. Aug 21, 20264 PRIMARY DOCUMENT EDGAR
  10. Aug 19, 2026SCHEDULE 13G/A EDGAR
  11. Aug 18, 20263 PRIMARY DOCUMENT EDGAR
  12. Aug 18, 20264 PRIMARY DOCUMENT EDGAR
  13. Aug 14, 2026SCHEDULE 13G/A EDGAR
  14. Aug 11, 20263 PRIMARY DOCUMENT EDGAR
  15. Aug 11, 20264 PRIMARY DOCUMENT EDGAR
  16. Aug 10, 20264 PRIMARY DOCUMENT EDGAR
  17. Aug 6, 202610-Q EDGAR
  18. Aug 6, 20268-K EDGAR
  19. Aug 6, 2026SCHEDULE 13G/A EDGAR
  20. Jul 30, 20264 EDGAR

The 429 filings since October 2021 can be filtered by form type and year here when JavaScript is on.

Every filing from the last five years, summarized. The full record is on SEC EDGAR.

Insider trades

123 open-market trades by officers, directors and large owners since October 2021: 17 buys and 106 sales. Grants, option exercises and gifts are left out.

DateWhoTradeSharesPriceValueFiling
Sep 29, 2026SCULLY WILLIAM P10% ownerBuy162,000$8.68$1.4MForm 4
Sep 28, 2026SCULLY WILLIAM P10% ownerBuy103,500$8.60$890.1KForm 4
Sep 18, 2026SCULLY WILLIAM P10% ownerBuy100,000$8.43$843.0KForm 4
Sep 2, 2026SCULLY WILLIAM P10% ownerBuy27,000$9.47$255.7KForm 4
Aug 20, 2026SCULLY WILLIAM P10% ownerBuy50,000$8.79$439.5KForm 4
Aug 7, 2026SCULLY WILLIAM P10% ownerBuy37,500$8.62$323.2KForm 4
Jul 29, 2026Kingston Anne EvansChief Strategy OfficerSale7,662$8.47$64.9KForm 4
Jul 29, 2026Isaacs Michael JohnGeneral Counsel & Company Sec.Sale8,386$8.47$71.0KForm 4
Jun 16, 2026SCULLY WILLIAM P10% ownerBuy20,000$7.90$158.0KForm 4
Jun 11, 2026SCULLY WILLIAM P10% ownerBuy125,000$8.17$1.0MForm 4
Jun 4, 2026SCULLY WILLIAM P10% ownerBuy50,000$9.31$465.5KForm 4
Jun 2, 2026SCULLY WILLIAM P10% ownerBuy50,000$9.43$471.5KForm 4
May 22, 2026SCULLY WILLIAM P10% ownerBuy100,000$9.81$981.0KForm 4
May 6, 2025EcoR1 Capital, LLC10% ownerSale1,984,053$7.64$15.2MForm 4
May 5, 2025EcoR1 Capital, LLC10% ownerSale977,693$8.11$7.9MForm 4
May 2, 2025EcoR1 Capital, LLC10% ownerSale3,317,938$8.36$27.7MForm 4
Jan 14, 2025SCULLY WILLIAM P10% ownerBuy100,000$12.79$1.3MForm 4
Dec 31, 2024SCULLY WILLIAM P10% ownerBuy32,000$13.01$416.5KForm 4
Dec 20, 2024SCULLY WILLIAM P10% ownerBuy2,000$15.91$31.8KForm 4
Dec 18, 2024SCULLY WILLIAM P10% ownerBuy73,436$13.93$1.0MForm 4

All 123 trades can be filtered by person here when JavaScript is on.

From Forms 4 filed with the SEC.

Major holders

Investors who own more than 5% of the shares must tell the SEC: a 13D if they may seek to influence the company, a 13G if they hold passively.

Sources

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