U.S. spot-Bitcoin ETFs recorded withdrawals for a second consecutive session, interrupting a strong September run of institutional buying as Bitcoin fell below $80,000. Onchain Lens reported $147.3 million in combined outflows across two sessions, including $100.7 million on Sept. 9 after $46.6 million the prior session, while other reports put the two-day total at $166.8 million across Sept. 9 and Sept. 10, including $120.2 million on Sept. 10. Grayscale's GBTC led reported fund-level selling on Sept. 8 with about $65.5 million in outflows, while BlackRock's IBIT and Bitwise's BITB recorded inflows. Despite the pullback, Onchain Lens estimated that spot-Bitcoin ETFs retained roughly $622.7 million in net September inflows, supported by approximately $731 million of inflows on Sept. 3. Rising Treasury yields, Brent crude above $100 per barrel and uncertainty over the Federal Reserve's next policy decision added pressure to risk appetite.