The extreme rarity of magnitude 8.0+ earthquakes, which occur globally only once every several years on average, combined with stable current seismic patterns, underpins the 89% market-implied probability against a megaquake by June 30. USGS data through mid-May 2026 show no active precursors such as accelerated subduction-zone slip or widespread foreshock sequences, following the normalization of the brief 1% short-term risk elevation after April’s magnitude 7.7 event off northern Japan. Historical analogs confirm that even in high-strain regions like the Cascadia or Japan trenches, the probability remains low over a six-week window absent clear geophysical indicators. Continuous real-time monitoring by the USGS and similar agencies provides ongoing verification, with any significant model shifts or new observations expected to influence trader sentiment only if they alter baseline tectonic assessments.