USGS seismic analysis establishes that magnitude 10.0 or larger earthquakes cannot occur because no known fault extends far enough to release the required energy, with the physical upper limit tied to rupture length along subduction zones. The 1960 Valdivia event at 9.5 remains the verified global maximum, and ongoing USGS monitoring through September 2026 shows only typical activity well below this threshold with no precursors for an unprecedented rupture. The brief window remaining until year-end further cements trader consensus on the No outcome at 99.3% implied probability. While theoretical revisions to magnitude scaling or discovery of an unknown planetary-scale fault could theoretically intervene, such developments lack any supporting geophysical evidence.