Bitcoin spot ETFs post $463M weekly net outflow, first downturn in flows since June

Bitcoin spot ETFs saw a $463 million net outflow in the week ended Sept. 14, marking the first week of negative flows since the June trough, according to Wintermute OTC trader @Jjay_dm. ARK and Grayscale accounted for $371 million of the withdrawals, while BlackRock's flows were unchanged. Bitcoin slid 4.4% on the week to close at $76,838, making it the worst-performing major asset. Ethereum fell 1.5%, while altcoins as a group gained 1.0%. Macro data added pressure on risk assets. U.S. August CPI rose 0.4% month over month, with core CPI up 0.3%, both above the 0.2% consensus. Producer prices accelerated, with PPI rising to a 5.4% annual rate. Goldman Sachs shifted its September call from "on hold" to "hike," and markets now price an 87% probability of a 25-basis-point increase at Wednesday's decision. Geopolitical risks also remained elevated. Middle East tensions intensified, Brent crude climbed above $105 a barrel, and the 10-year U.S. Treasury yield touched a 20-year high. Wintermute said the turn to ETF outflows has pushed market positioning back to neutral from bullish. Two events are in focus this week: (1) Tuesday's U.S. Senate procedural vote on the CLARITY Act (Crypto Market Structure Act), which requires 60 votes to advance; and (2) Wednesday's Federal Reserve rate decision. While a hike is largely priced in, any hawkish guidance—especially signals pointing to continued rate increases into Q1 2027—could weigh on crypto markets.