PRTA earnings date, and what happened the last 4 times

Next report

Thu Nov 5

Quality Score today 4

After the close, in 10 days. Expected: the company has not confirmed it.

PRTA closed higher after 3 of its last 4 reports. On average it closed +2.2% the session after a report.

The moment PRTA reports

Its figures, in plain words
How it moves after, beside its last four
Its Quality Score going in, and after

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What happened after PRTA's last 4 reports

PRTA's last 4 earnings reports
Reported	Score going in	Gap	Reaction	5 sessions
Aug 6, 20262026 · After close	1estimated	-0.5%	+2.1%	+5.8%
May 7, 20262026 · After close	3estimated	+4.6%	+2.0%	-6.3%
Feb 19, 20262026 · After close	-7estimated	+3.9%	-0.1%	-4.3%
Nov 6, 20252025 · After close	-1estimated	+4.1%	+4.8%	+1.0%

Aug 6, 2026, after the close: the next session PRTA opened -0.5% and closed +2.1%, and five sessions on it stood +5.8%. Its Quality Score going in was 1 (Below Average), estimated.
May 7, 2026, after the close: the next session PRTA opened +4.6% and closed +2.0%, and five sessions on it stood -6.3%. Its Quality Score going in was 3 (Below Average), estimated.
Feb 19, 2026, after the close: the next session PRTA opened +3.9% and closed -0.1%, and five sessions on it stood -4.3%. Its Quality Score going in was -7 (Poor), estimated.
Nov 6, 2025, after the close: the next session PRTA opened +4.1% and closed +4.8%, and five sessions on it stood +1.0%. Its Quality Score going in was -1 (Poor), estimated.

Across these 4 reports PRTA opened higher after 3 of 4 and closed higher after 3 of 4; on average it opened +3.0%, closed +2.2%, and stood -0.9% five sessions on. Its Quality Score is 4 today, against 1 going into its Aug 6, 2026 report.

Gap: where the stock opened the session after the report. Reaction: where that session closed. Both against the close before the report. The largest of the 4: +4.8% after the Nov 6, 2025 report. A score marked estimated was worked out afterwards from that day's prices and filings; Breakaway has recorded every score live since Sep 9 2026.

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Questions about PRTA's earnings

As of Oct 26, 2026: Prothena (PRTA): expected to report Thu Nov 5, after the close. PRTA closed higher after 3 of its last 4 reports. Its Quality Score is 4 (Below Average). Scores as of 11:11 PM ET, 15 minutes behind.

When is PRTA's next earnings date?

Expected to report Thu Nov 5, after the close, a date Breakaway expects from the company's usual timing; the company has not confirmed it. PRTA closed higher after 3 of its last 4 reports. Past behavior, not a forecast.

Does PRTA report before or after the market?

PRTA is expected to report Thu Nov 5, after the close. Its last 4 reports came after the close.

How did PRTA stock react to its last earnings report?

Aug 6, 2026, after the close: the next session PRTA opened -0.5% and closed +2.1%, and five sessions on it stood +5.8%.

Does PRTA stock usually go up after earnings?

PRTA closed higher after 3 of its last 4 reports. On average it closed +2.2% the session after a report, after opening +3.0%. Past behavior, not a forecast.

Prothena's page has its Quality Score, its chart, and its insiders' trades. Everyone reporting beside it: next week's earnings.