This market will resolve to the bracket containing the magnitude of the largest earthquake recorded globally on October 20, 2026, as reported by the USGS Earthquake Catalog.
Leading outcome
98%
98%
2 outcomes
Yes
No
Now Gained in 24h Lost in 24hChanges are in percentage points (pp).
Latest update
SurgeMonitoring onlyThe tracked probability rose to 98.1%, up 20.8 percentage points from 77.3% in the latest observation window. No evidence-qualified public source was supplied, so this remains a monitoring note rather than a causal explanation.
Yes: 77% → 98%
+20.8 ppOdds chart
Living timeline
Observed movement
Observed probability rose from 77.3% to 98.1% (+20.8 percentage points), from 2026-10-20T13:15:37.074Z to 2026-10-20T13:32:57.562Z (UTC).
Editorial research is deferred. This update preserves the observed market change. The cause of the move is not established.
The measured move
Yes: 77.3% → 98.1%
Probability moved from 77.3% to 98.1% (+20.8 percentage points). Observations were 17 minutes 20 seconds apart: 2026-10-20 13:15:37 UTC to 2026-10-20 13:32:57 UTC.
Watch further market observations and reporting about this contract. This update has not been enrolled for editorial research.
No external sources are attached yet.
Observed movement
Observed probability fell from 87.8% to 75.1% (-12.7 percentage points), from 2026-10-20T10:00:36.194Z to 2026-10-20T10:17:52.816Z (UTC).
Observed movement
Observed probability rose from 75.15% to 87.5% (+12.35 percentage points), from 2026-10-20T09:32:17.451Z to 2026-10-20T09:46:45.843Z (UTC).
Observed movement
Observed probability rose from 51.5% to 74.9% (+23.4 percentage points), from 2026-10-20T07:45:09.424Z to 2026-10-20T08:01:12.859Z (UTC).
Observed movement
Observed probability fell from 75.3% to 51.5% (-23.8 percentage points), from 2026-10-20T07:17:05.181Z to 2026-10-20T07:31:48.077Z (UTC).
Observed movement
Observed probability fell from 97.15% to 74.65% (-22.5 percentage points), from 2026-10-20T05:32:51.585Z to 2026-10-20T05:47:09.607Z (UTC).
Market rules, made readable
Official descriptionRead the rules before reading the headline. Resolution wording decides the outcome, not the news.
This market will resolve to the bracket containing the magnitude of the largest earthquake recorded globally on October 20, 2026, as reported by the USGS Earthquake Catalog. Brackets: Under 5.3 / 5.3 to 5.4 / 5.5 to 5.6 / 5.7 to 5.8 / 5.9 to 6.0 / 6.1 or more. Exactly one bracket resolves "Yes". The observation period is the UTC calendar day: 00:00 UTC to 23:59 UTC on October 20, 2026.
An earthquake is assigned to the day containing its origin time. Magnitude refers to the USGS preferred magnitude value, listed under 'Magnitude' in the format column. If USGS revises a magnitude after initial publication, the revision governs provided it is published before 2:00 PM ET on October 21, 2026. A value first published after that time is not considered.
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Source market
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Story so far
MonitoringPolySays is monitoring this market.
No evidence-qualified explanation has been published yet.
No evidence logged yet. No catalyst, open question, or public source is attached to this story, and we won’t guess.
If the reported magnitude carries more than one decimal place, it is rounded to the nearest tenth using standard rounding conventions (0.05 rounds up). Brackets are inclusive of their stated endpoints. If no earthquake data for October 20, 2026 has been published by 2:00 PM ET on October 21, 2026, this market will resolve to the "Under 5.3" bracket.
The resolution source for this market is the USGS Earthquake Catalog, maintained by the United States Geological Survey, at.