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PRTA
Volume: 401.93K

Prothena (PRTA) Market Capitalization Overview

Market Cap: $494.70M as of Jan 9, 2026

$494.70M
$82.90M (14.35%)past month
As of Jan 9, 2026, Prothena (PRTA) has a market capitalization of $494.70M. Over the past 30 days, its market cap has decreased by -10.42%, while in the last 12 months, it has decreased by -3.77%.

Market capitalization represents the total value of Prothena as perceived by the stock market. It is calculated by multiplying the current stock price by the total number of outstanding shares.

Prothena (PRTA) Market Cap Formula = Stock Price * Shares Outstanding

The market cap of Prothena (PRTA) helps investors assess the company's size and compare it with competitors for better investment decisions.

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Prothena (PRTA) Market Cap History

DateMarket CapChange
Dec 1, 2025$552.84M-2.56%
Nov 3, 2025$567.37M+6.25%
Oct 1, 2025$533.99M+19.95%
Sep 2, 2025$445.18M+21.45%
Aug 1, 2025$366.57M+8.79%
Jul 1, 2025$336.96M+34.33%
Jun 2, 2025$250.84M-46.56%
May 1, 2025$469.38M-25.72%
Apr 1, 2025$631.93M-18.07%
Mar 3, 2025$771.35M+6.66%
Feb 3, 2025$723.19M-1.68%
Jan 2, 2025$735.57M-8.87%

Prothena (PRTA) End of Year Market Cap History

DateMarket CapChange
2026$494.70M-3.77%
2025$514.08M-31.02%
2024$745.26M-61.79%
2023$1.96B-37.30%
2022$3.12B+35.14%
2021$2.31B—

FAQs About Prothena (PRTA) Market Cap

As of Jan 9, 2026, the market capitalization of Prothena (PRTA) is $494.70M. Market cap represents the total value of a company’s outstanding shares and is a key indicator of its size in the stock market.

In the last 30 days, Prothena’s market capitalization has decreased by -14.35%, changing from $577.60M to $494.70M as of Jan 9, 2026.

In the last 3 months, Prothena’s market capitalization has increased by —, changing from – to – as of –.

In the year 2025, Prothena’s market capitalization decreased from $745.26M in January to $514.08M in December, reflecting a -31.02% change.

In the past five years, Prothena (PRTA) has had a compound annual growth rate (CAGR) of -25.90% in market capitalization. This means its market cap has shrunk at an average rate of -25.90% per year.

Prothena (PRTA)

Volume: 401.93K

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