PRTAProthena Corporation plc
What is the market doing?
In a downtrend (−7% vs 200-day). That is the only one of 3 checks this filer's data supports, so take it as a single data point rather than a settled answer.
In a downtrend, below its 50- and 200-day averages. Price is −7% vs its 200-day average.
Where this answer is blind. Insider selling is often routine (taxes, diversification); only cluster buying is a strong tell.
How PRTA is trading
Prothena Corporation plc is −15% over the past year while the S&P 500 is +18%: 34 points behind the market. Through the fall, its own insiders bought $3.1M more stock than they sold.
1-year return · S&P 500 +18%
- vs 200-day average
- −7.4%
vs 200-day average · below trend, but not far
- RSI (14)
- 51
RSI (14) · neutral
- Below its 52-week high
- 25%
Below its 52-week high
Details›
- Last close2026-10-08
- $8.61
- 1 monthS&P 500 +1.6%
- −7.4%
- 1 yearS&P 500 +18%
- −15%
- 5 yearsS&P 500 +86%
- −88%
- vs 50-day average$8.86
- −2.8%
- 52-week high
- $11.51
- 52-week low
- $7.91
- Annualised volatility
- 64%
- Insider buying, net, 6 monthsForms 3/4/5 to 2026-10-08
- $3.1M
| Year | Return |
|---|---|
| 2026 (year to date) | −9.8% |
| 2025 | −31% |
| 2024 | −62% |
| 2023 | −40% |
| 2022 | +22% |
| 2021 | +311% |
| 2020 | −24% |
| 2019 | +54% |
| 2018 | −73% |
| 2017 | −24% |
| Month | Years | Positive | Average |
|---|---|---|---|
| Jan | 10 | 3 of 10 | −6.9% |
| Feb | 10 | 5 of 10 | +11% |
| Mar | 10 | 5 of 10 | −2.0% |
| Apr | 10 | 4 of 10 | −12% |
| May | 10 | 4 of 10 | −3.5% |
| Jun | 10 | 6 of 10 | +13% |
| Jul | 11 | 8 of 11 | +9.1% |
| Aug | 11 | 5 of 11 | +1.6% |
| Sep | 11 | 5 of 11 | +7.5% |
| Oct | 11 | 6 of 11 | −3.8% |
| Nov | 10 | 4 of 10 | +2.2% |
| Dec | 10 | 3 of 10 | −4.0% |
End-of-day closes from IEX; the S&P 500 comparison uses SPY over the same window. Prices are a reference point, not a basis for trading decisions.