Prothena Corp Public (PRTA) Common Equity (2012 - 2026)
Prothena Corp Public's Common Equity came in at $286.89 million for Q2 2026, down 11.5% from $324.33 million a year earlier and down 8.2% from the prior quarter.
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Analysis
Prothena Corp Public (PRTA) Common Equity (2012 - 2026) Analysis & Trends
At the end of FY2025, Prothena Corp Public's Common Equity was $280.47 million, down 42.4% from FY2024.
- Common Equity has declined in each of the last three years, though with a five-year compound annual growth rate of 8.8% (FY2020 to FY2025).
- Going back by year, Common Equity was $486.93 million in FY2024 (-13.3%), $561.37 million in FY2023 (-9.8%), $622.04 million in FY2022 (+33.5%) and $466.04 million in FY2021 (+153.3%).
- The five-year range for quarterly Common Equity is $280.47 million (Q4 2025) to $622.04 million (Q4 2022).
- Year-over-year, Common Equity has declined for eight consecutive quarters, with an average decline of 26.4% over the last eight quarters.
- The fastest year-over-year change in Common Equity over five years came in Q4 2021 (growth of 153.3%), and the weakest in Q3 2025 (a decline of 44.8%).
- Business Quant data shows PRTA's Common Equity at $312.62 million (Q1 2026), $280.47 million (Q4 2025) and $294.99 million (Q3 2025) in the three quarters before Q2 2026.
Peer Set
Peer Comparison
| # | Company | Market Cap | Enterprise Value | Gross Profit (Qtr) | Common Equity (Qtr) |
|---|---|---|---|---|---|
| 1 | Johnson & Johnson | 655.56 Bn | 574.09 Bn | 17.26 Bn | 84.97 Bn |
| 2 | AbbVie | 470.94 Bn | 444.10 Bn | 12.70 Bn | -5.94 Bn |
| 3 | Merck | 367.14 Bn | 321.57 Bn | 12.21 Bn | 41.98 Bn |
| 4 | Novartis Ag | 280.33 Bn | 236.20 Bn | 11.24 Bn | 41.95 Bn |
| 5 | Astrazeneca | 257.78 Bn | 231.34 Bn | 12.86 Bn | 50.37 Bn |
| 6 | Amgen | 226.04 Bn | 181.44 Bn | 7.24 Bn | 11.69 Bn |
| 7 | Gilead Sciences | 188.89 Bn | 163.01 Bn | 6.22 Bn | 11.83 Bn |
| 8 | Pfizer | 163.75 Bn | 110.70 Bn | 10.94 Bn | 85.49 Bn |
| 9 | Vertex Pharmaceuticals | 133.68 Bn | 105.69 Bn | 2.84 Bn | 20.25 Bn |
| 10 | Prothena Corp Public | 451.21 Mn | -804.86 Mn | - | 286.89 Mn |
Historic Data
Download Data
Historic Data
| Date | Value |
|---|---|
| Jun 30, 2026 | 286.89 Mn |
| Mar 31, 2026 | 312.62 Mn |
| Dec 31, 2025 | 280.47 Mn |
| Sep 30, 2025 | 294.99 Mn |
| Jun 30, 2025 | 324.33 Mn |
| Mar 31, 2025 | 437.68 Mn |
| Dec 31, 2024 | 486.93 Mn |
| Sep 30, 2024 | 534.36 Mn |
| Jun 30, 2024 | 581.92 Mn |
| Mar 31, 2024 | 502.40 Mn |
| Dec 31, 2023 | 561.37 Mn |
| Sep 30, 2023 | 617.23 Mn |
| Jun 30, 2023 | 581.68 Mn |
| Mar 31, 2023 | 607.41 Mn |
| Dec 31, 2022 | 622.04 Mn |
| Sep 30, 2022 | 404.65 Mn |
| Jun 30, 2022 | 407.30 Mn |
| Mar 31, 2022 | 438.89 Mn |
| Dec 31, 2021 | 466.04 Mn |
| Sep 30, 2021 | 490.47 Mn |
API Access
Prothena Corp Public Common Equity 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=common-equity&ticker=PRTA&period=max&api_key=YOUR_API_KEYimport requests
url = "https://data.businessquant.com/historic"
params = {"slug": "common-equity", "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=common-equity&ticker=PRTA&period=max&api_key=YOUR_API_KEY");
const data = await res.json();