Binance SOXL perpetual mark drops 5.9% despite 3% price band constraint

During the 21:00-22:00 UTC hour on Oct. 17, Binance's SOXLUSDT perpetual mark price fell 5.9% from opening to low, while the reference index declined 3.9%. All 60 sampled minute-close gaps between the mark and index remained within the 3% weekend limit, but the index itself moved significantly, leaving leveraged traders exposed to cumulative losses and liquidation risk despite the narrow mark/index spread.