BlackRock’s iShares Bitcoin Trust (IBIT) is approaching the $100B AUM mark and—if it closes above it—would set a speed record for ETFs reaching that level. Numbers and pace Launched in January 2024, IBIT has scaled to the threshold in under two years, surpassing the multi-year timelines typical of prior large ETFs. Structure and mechanics IBIT is a spot Bitcoin ETF. Primary market creations/redemptions occur in-kind with BTC via authorized participants, so sustained net creations reflect incremental coin demand alongside price effects. Market context Strong, recurring inflows into U.S. spot Bitcoin ETFs, institutional adoption, and IBIT’s liquidity advantages have reinforced a flywheel of tighter spreads and deeper depth relative to peers.