Nasdaq · PRTA · stock
Prothena Corp. Public Ltd. Co. (PRTA) stock price history
Every Nasdaq trading session of Prothena Corp. Public Ltd. Co. from Dec 21, 2012 to Sep 28, 2026: 3,461 daily bars, adjusted for splits and dividends, with minute bars from Jul 13, 2026 forward. The full series is served by the API: a free key covers the last year, paid plans the whole history and minute bars.
PRTA adjusted close, 2012 to 2026
- $78.89
- All time high, 2021
- $11.80
- 52 week high, $7.73 low
- 3,461
- Daily sessions since 2012
Last updated Sep 28, 2026, the last stored session. Refreshes after each trading day. Full 2012 to 2026 series and minute bars.
PRTA key facts
- Prothena Corp. Public Ltd. Co. (PRTA) closed at $8.72 on Sep 28, 2026 on Nasdaq.
- PRTA's all time high close is $78.89, set on Sep 23, 2021; its all time low close is $4.58 on May 27, 2025.
- PRTA's 52 week range is $7.73 to $11.80.
- PRTA returned -7.3% over the year to Sep 28, 2026 and -87.9% over five years.
- Over ten years PRTA returned -86%, -17.7% a year compounded.
- PRTA's deepest drawdown was -94.2% from Sep 23, 2021 to May 27, 2025.
- DataCedar holds 3,461 daily sessions of PRTA history from Dec 21, 2012 and minute bars from Jul 13, 2026, adjusted for splits and dividends, served by the API under a key.
PRTA price chart, 2012 to 2026
PRTA returns
Price return from the last close on or before the window start to Sep 28, 2026, on adjusted closes.
| Period | Return |
|---|---|
| 1 month | -6.5% |
| 3 months | -13.0% |
| 6 months | -5.8% |
| Year to date | -6.3% |
| 1 year | -7.3% |
| 3 years | -82.1% |
| 5 years | -87.9% |
| 10 years | -85.8% |
| Since Dec 21, 2012 | +21.1% |
| Compound annual growth, 13.8 years | +1.4% |
PRTA records
Measured on the stored closes; every figure is reproducible from the API series.
- All time high close
- $78.89 on Sep 23, 2021
- All time low close
- $4.58 on May 27, 2025
- 52 week high
- $11.80 on May 8, 2026
- 52 week low
- $7.73 on Jun 11, 2026
- Deepest drawdown
- -94.2% from Sep 23, 2021 to May 27, 2025, not yet recovered
- Best single session
- +87.5% on Sep 28, 2022
- Worst single session
- -68.8% on Apr 23, 2018
- Volatility, 1 year annualised
- 47.2%
- Sessions closing higher, 1 year
- 46%
- Best calendar year
- 2021, +311%
- Worst calendar year
- 2018, -73%
PRTA price history by year
Open is the first session's open, high and low span the year, close is the last session's close, and the return is close over the previous year's close. 2012 starts on Dec 21, 2012; 2026 runs to Sep 28, 2026.
| Year | Open | High | Low | Close | Return | Volume | Sessions |
|---|---|---|---|---|---|---|---|
| 2026 | $9.56 | $11.80 | $7.73 | $8.72 | -8.7% | 93.5M | 185 |
| 2025 | $14.01 | $16.67 | $4.32 | $9.55 | -31.0% | 234.8M | 250 |
| 2024 | $35.83 | $41.54 | $11.70 | $13.85 | -61.9% | 149.1M | 252 |
| 2023 | $60.77 | $79.65 | $28.51 | $36.34 | -39.7% | 133.6M | 250 |
| 2022 | $49.77 | $66.47 | $21.06 | $60.25 | +22.0% | 132.9M | 251 |
| 2021 | $12.19 | $79.75 | $10.72 | $49.40 | +311.3% | 106.1M | 252 |
| 2020 | $15.97 | $16.05 | $7.10 | $12.01 | -24.1% | 66.1M | 253 |
| 2019 | $10.16 | $17.63 | $6.71 | $15.83 | +53.7% | 68.5M | 252 |
| 2018 | $38.13 | $46.14 | $8.63 | $10.30 | -72.5% | 159.2M | 251 |
| 2017 | $50.07 | $70.00 | $34.85 | $37.49 | -23.8% | 75.8M | 251 |
| 2016 | $66.92 | $68.18 | $28.20 | $49.19 | -27.8% | 121.1M | 252 |
| 2015 | $21.00 | $76.42 | $18.76 | $68.11 | +228.1% | 102.1M | 252 |
| 2014 | $26.52 | $49.24 | $16.71 | $20.76 | -21.7% | 81.2M | 252 |
| 2013 | $7.50 | $30.55 | $5.64 | $26.52 | +261.8% | 30.3M | 252 |
| 2012 | $8.10 | $8.10 | $6.60 | $7.33 | n/a | 1.6M | 6 |
PRTA monthly closes, last 12 months
| Month | Month end close | Change |
|---|---|---|
| September 2026 | $8.72 | -6.7% |
| August 2026 | $9.35 | +15.1% |
| July 2026 | $8.12 | -17.1% |
| June 2026 | $9.79 | -3.8% |
| May 2026 | $10.18 | -8.0% |
| April 2026 | $11.06 | +13.8% |
| March 2026 | $9.72 | +12.1% |
| February 2026 | $8.67 | -1.6% |
| January 2026 | $8.81 | -7.7% |
| December 2025 | $9.55 | -11.2% |
| November 2025 | $10.75 | 0.0% |
| October 2025 | $10.75 | +10.1% |
About the PRTA data
Daily bars. 3,461 sessions from Dec 21, 2012 to Sep 28, 2026, one row per Nasdaq trading day with open, high, low, close and volume. Prices are adjusted for splits and cash dividends so the series is comparable across its whole length; the API also serves the raw, split only and dividend only views.
Minute bars. Stored from Jul 13, 2026 forward, most recent session Sep 28, 2026. Minute history is captured from the day collection began and is never backfilled, so this start date is exact. Five minute, fifteen minute and hourly bars are derived from these minutes.
Time and currency. Session dates are Nasdaq trading days; minute timestamps are UTC. Prices are in USD. Volume is shares traded on the session.
Get the data. The REST endpoint returns the daily series as JSON with pagination; a free key serves the last year, Quant and above the full history back to Dec 21, 2012, and minute bars come with the paid windows. It takes timeframe (1Min, 5Min, 15Min, 1Hour, 1Day), adjustment, start and end. See the bars endpoint and authentication, and pricing for the plan windows.
curl "https://api.datacedar.com/v3/stocks/PRTA/bars?timeframe=1Day&adjustment=all&limit=50000" \
-H "X-API-Key: YOUR_KEY"Nearby on Nasdaq
Common questions
PRTA share price history
