US spot Bitcoin ETFs recorded a $450.4 million net outflow on September 15, erasing the prior session’s $159.9 million inflow, according to Farside data. The reversal marks the latest swing in a volatile week for institutional Bitcoin products ahead of the Federal Reserve’s policy decision.
The outflow caps a six-session stretch since September 8 that has seen $753 million in net withdrawals across spot ETFs. Bitcoin traded at $75,900 at the time of reporting, having navigated mixed institutional positioning across spot and derivatives markets.
Derivatives Pressure Mounts
Spot cumulative volume delta fell to negative $142 million, breaching Glassnode’s lower statistical band of negative $115 million. The metric, which measures aggressive buying relative to aggressive selling, signals concentrated selling pressure in the spot market.
Perpetual futures showed sharper stress. Cumulative volume delta in perpetuals dropped to negative $605 million, well below the lower band of negative $233 million, indicating aggressive selling in leveraged positions. Futures open interest eased from $37 billion to $36.4 billion but remained above its upper statistical band of $36 billion, suggesting persistent long exposure despite recent liquidations.
Long-side funding payments rose to $1.4 million while staying within normal statistical range, according to Glassnode’s snapshot. The data predates Farside’s September 15 ETF flow update.
Timing and Causation Remain Unclear
The temporal coincidence of ETF redemptions and exchange selling has raised questions about their relationship. However, any causal link between ETF redemptions and exchange selling remains unresolved, as ETF net flows measure creations and redemptions across funds without revealing investor identities or direct Bitcoin sale execution.
Bitcoin’s first test following the Federal Reserve’s policy decision was still ahead at the time of reporting. The two-day Fed meeting was in progress during the reporting window.
