Prothena Corporation plc (PRTA)
Showing Closing Date Range from Apr 19 to Oct 16, 2026 compared to Oct 20, 2025 to Apr 18, 2026.
Compare Last 6 Months with Previous Period
Investor Relations:ir.prothena.com
Current Period Close
$8.35
Apr 19, 2026 - Oct 16, 2026
Previous Period Close
$10.90
Oct 20, 2025 - Apr 18, 2026
Net Comparison Delta
$-2.55 (-23.39%)
Relative performance vs prior benchmark
Historical Quotes & Breakdown(122 dates)
| Current Date | Current Close | Previous Date | Previous Close | Delta (%) |
|---|---|---|---|---|
| Oct 16, 2026 | $8.35 | Apr 15, 2026 | $10.82 | -22.83% |
| Oct 15, 2026 | $8.50 | Apr 14, 2026 | $10.61 | -19.89% |
| Oct 14, 2026 | $8.37 | Apr 13, 2026 | $10.31 | -18.82% |
| Oct 13, 2026 | $8.36 | Apr 10, 2026 | $10.50 | -20.38% |
| Oct 12, 2026 | $8.43 | Apr 09, 2026 | $10.58 | -20.32% |
| Oct 09, 2026 | $8.84 | Apr 08, 2026 | $10.65 | -17.00% |
| Oct 08, 2026 | $8.61 | Apr 07, 2026 | $10.36 | -16.89% |
| Oct 07, 2026 | $8.48 | Apr 06, 2026 | $10.04 | -15.54% |
| Oct 06, 2026 | $8.02 | Apr 02, 2026 | $9.86 | -18.66% |
| Oct 05, 2026 | $8.27 | Apr 01, 2026 | $10.03 | -17.55% |
| Oct 02, 2026 | $8.36 | Mar 31, 2026 | $9.72 | -13.99% |
| Sep 25, 2026 | $8.29 | Mar 30, 2026 | $9.25 | -10.38% |
| Sep 24, 2026 | $8.32 | Mar 27, 2026 | $9.26 | -10.15% |
| Sep 23, 2026 | $8.68 | Mar 26, 2026 | $9.52 | -8.82% |
| Sep 22, 2026 | $8.99 | Mar 25, 2026 | $9.31 | -3.44% |
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