Prothena Corp Public (PRTA) Market Capitalization (2012 - 2026)
Prothena Corp Public's Market Capitalization was $506.58 million in Q2 2026, up 55.0% from $326.73 million a year earlier but down 1.8% from the prior quarter.
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Analysis
Prothena Corp Public (PRTA) Market Capitalization (2012 - 2026) Analysis & Trends
For FY2025, Market Capitalization at Prothena Corp Public came in at $514.1 million, down 31.0% from FY2024.
- Market Capitalization has now declined for three consecutive years, though with a five-year compound annual growth rate of 1.4% (FY2020 to FY2025).
- In earlier years, Market Capitalization was $745.5 million in FY2024 (-61.8%), $1.95 billion in FY2023 (-37.9%), $3.14 billion in FY2022 (+36.2%) and $2.31 billion in FY2021 (+380.8%).
- Quarterly Market Capitalization has moved between $326.73 million (Q2 2025) and $3.65 billion (Q2 2023) over five years.
- Compared with a year earlier, Market Capitalization was higher in 1 of the last eight quarters, with an average decline of 36.0%.
- The best year-over-year quarter for Market Capitalization over five years was Q3 2021 (growth of 731.1%); the worst was Q2 2025 (a decline of 70.6%).
- Per Business Quant data, PRTA's Market Capitalization in the three quarters before Q2 2026 was $515.91 million (Q1 2026), $514.1 million (Q4 2025) and $525.38 million (Q3 2025).
Peer Set
Peer Comparison
| # | Company | Market Cap | Enterprise Value | Gross Profit (Qtr) |
|---|---|---|---|---|
| 1 | Johnson & Johnson | 655.56 Bn | 574.09 Bn | 17.26 Bn |
| 2 | AbbVie | 470.94 Bn | 444.10 Bn | 12.70 Bn |
| 3 | Merck | 367.14 Bn | 321.57 Bn | 12.21 Bn |
| 4 | Novartis Ag | 280.33 Bn | 236.20 Bn | 11.24 Bn |
| 5 | Astrazeneca | 257.78 Bn | 231.34 Bn | 12.86 Bn |
| 6 | Amgen | 226.04 Bn | 181.44 Bn | 7.24 Bn |
| 7 | Gilead Sciences | 188.89 Bn | 163.01 Bn | 6.22 Bn |
| 8 | Pfizer | 163.75 Bn | 110.70 Bn | 10.94 Bn |
| 9 | Vertex Pharmaceuticals | 133.68 Bn | 105.69 Bn | 2.84 Bn |
| 10 | Prothena Corp Public | 451.21 Mn | -804.86 Mn | - |
Historic Data
Download Data
Historic Data
| Date | Value |
|---|---|
| Jun 30, 2026 | 506.58 Mn |
| Mar 31, 2026 | 515.91 Mn |
| Dec 31, 2025 | 514.10 Mn |
| Sep 30, 2025 | 525.38 Mn |
| Jun 30, 2025 | 326.73 Mn |
| Mar 31, 2025 | 666.38 Mn |
| Dec 31, 2024 | 745.50 Mn |
| Sep 30, 2024 | 900.22 Mn |
| Jun 30, 2024 | 1.11 Bn |
| Mar 31, 2024 | 1.33 Bn |
| Dec 31, 2023 | 1.95 Bn |
| Sep 30, 2023 | 2.59 Bn |
| Jun 30, 2023 | 3.65 Bn |
| Mar 31, 2023 | 2.55 Bn |
| Dec 31, 2022 | 3.14 Bn |
| Sep 30, 2022 | 2.90 Bn |
| Jun 30, 2022 | 1.27 Bn |
| Mar 31, 2022 | 1.71 Bn |
| Dec 31, 2021 | 2.31 Bn |
| Sep 30, 2021 | 3.31 Bn |
API Access
Prothena Corp Public Market Capitalization API
Pull this series into your own models, spreadsheets and apps with the Business Quant
Historical Metrics API. The request below matches the chart above — change the
frequency, period or values and it follows. Swap YOUR_API_KEY for your own key.
https://data.businessquant.com/historic?slug=market-capitalization&ticker=PRTA&period=max&api_key=YOUR_API_KEYimport requests
url = "https://data.businessquant.com/historic"
params = {"slug": "market-capitalization", "ticker": "PRTA", "period": "max", "api_key": "YOUR_API_KEY"}
data = requests.get(url, params=params).json()const res = await fetch("https://data.businessquant.com/historic?slug=market-capitalization&ticker=PRTA&period=max&api_key=YOUR_API_KEY");
const data = await res.json();