The absence of any known fault long enough to generate a magnitude 10 earthquake underpins the 99% market-implied odds against occurrence before 2027. USGS assessments confirm that a rupture of this scale would require a fault spanning most of the planet, far exceeding the roughly 1,000-mile length tied to the 1960 Chile event—the largest instrumentally recorded at magnitude 9.5. No subduction zone or other tectonic setting currently shows the necessary extent or stress accumulation for such an event, and global seismic monitoring reveals no precursors approaching this threshold. While asteroid impacts or other planetary-scale disruptions could theoretically exceed mid-9 magnitudes, these remain statistically negligible within the brief remaining window.