Prothena Corp Public (PRTA) Shares Outstanding (2012 - 2026)
Prothena Corp Public's Shares Outstanding was 52.15 million in Q2 2026, down 3.1% from 53.83 million a year earlier and down 2.9% from the prior quarter.
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Analysis
Prothena Corp Public (PRTA) Shares Outstanding (2012 - 2026) Analysis & Trends
For FY2025, Shares Outstanding at Prothena Corp Public came in at 53.83 million, up 0.1% from FY2024.
- Shares Outstanding has now increased for 14 consecutive years, with a five-year compound annual growth rate of 6.2% (FY2020 to FY2025).
- In earlier years, Shares Outstanding was 53.77 million in FY2024 (+1.0%), 53.22 million in FY2023 (+12.3%), 47.37 million in FY2022 (+7.1%) and 44.23 million in FY2021 (+10.8%).
- The Q2 2026 figure marks the lowest quarterly Shares Outstanding since Q4 2022.
- Compared with a year earlier, Shares Outstanding was higher in six of the last eight quarters, with an average decline of 0.2%.
- The best year-over-year quarter for Shares Outstanding over five years was Q1 2022 (growth of 16.0%); the worst was Q2 2026 (a decline of 3.1%).
- Per Business Quant data, PRTA's Shares Outstanding in the three quarters before Q2 2026 was 53.71 million (Q1 2026), 53.83 million (Q4 2025) and 53.83 million (Q3 2025).
Peer Set
Peer Comparison
| # | Company | Market Cap | Enterprise Value | Gross Profit (Qtr) | Shares Outstanding (Qtr) |
|---|---|---|---|---|---|
| 1 | Johnson & Johnson | 638.12 Bn | 556.64 Bn | 17.26 Bn | 2.41 Bn |
| 2 | AbbVie | 462.60 Bn | 435.75 Bn | 12.70 Bn | 1.77 Bn |
| 3 | Merck | 358.70 Bn | 313.13 Bn | 12.21 Bn | 2.47 Bn |
| 4 | Novartis Ag | 272.16 Bn | 228.03 Bn | 11.24 Bn | 1.94 Bn |
| 5 | Astrazeneca | 250.36 Bn | 223.92 Bn | 12.86 Bn | 1.55 Bn |
| 6 | Amgen | 227.87 Bn | 183.27 Bn | 7.24 Bn | 540.00 Mn |
| 7 | Gilead Sciences | 184.97 Bn | 159.08 Bn | 6.22 Bn | 1.24 Bn |
| 8 | Pfizer | 162.61 Bn | 109.56 Bn | 10.94 Bn | 5.70 Bn |
| 9 | Vertex Pharmaceuticals | 132.45 Bn | 104.46 Bn | 2.84 Bn | 253.70 Mn |
| 10 | Prothena Corp Public | 433.62 Mn | -822.46 Mn | - | 52.15 Mn |
Historic Data
Download Data
Historic Data
| Date | Value |
|---|---|
| Jun 30, 2026 | 52.15 Mn |
| Mar 31, 2026 | 53.71 Mn |
| Dec 31, 2025 | 53.83 Mn |
| Sep 30, 2025 | 53.83 Mn |
| Jun 30, 2025 | 53.83 Mn |
| Mar 31, 2025 | 53.83 Mn |
| Dec 31, 2024 | 53.77 Mn |
| Sep 30, 2024 | 53.79 Mn |
| Jun 30, 2024 | 53.77 Mn |
| Mar 31, 2024 | 53.71 Mn |
| Dec 31, 2023 | 53.22 Mn |
| Sep 30, 2023 | 53.56 Mn |
| Jun 30, 2023 | 53.12 Mn |
| Mar 31, 2023 | 52.50 Mn |
| Dec 31, 2022 | 47.37 Mn |
| Sep 30, 2022 | 46.99 Mn |
| Jun 30, 2022 | 46.81 Mn |
| Mar 31, 2022 | 46.70 Mn |
| Dec 31, 2021 | 44.23 Mn |
| Sep 30, 2021 | 45.63 Mn |
API Access
Prothena Corp Public Shares Outstanding 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=shares-outstanding&ticker=PRTA&period=max&api_key=YOUR_API_KEYimport requests
url = "https://data.businessquant.com/historic"
params = {"slug": "shares-outstanding", "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=shares-outstanding&ticker=PRTA&period=max&api_key=YOUR_API_KEY");
const data = await res.json();