They have now shed more than $147 million, which can be potentially interpreted as a sign of waning institutional demand.
This comes after Bitcoin ETFs attracted substantial fresh capital earlier in the month.
Strong September start loses momentum
September had a very strong start. On Sept. 3 alone, U.S. spot Bitcoin products attracted roughly $731 million, according to industry flow trackers.
The inflows came as Bitcoin rallied back above $80,000 amid renewed optimism surrounding monetary policy and cryptocurrency regulation.
However, institutional demand weakened sharply after the long U.S. holiday weekend.
SoSoValue data showed that the ETFs posted $46.65 million in net redemptions on Sept. 8.
Grayscale's GBTC makes up a substantial portion of selling with roughly $65.5 million in outflows. Fidelity's FBTC and Invesco's BTCO also recorded withdrawals.
Those losses were partially offset by inflows into several competing products. BlackRock's IBIT attracted around $10.7 million. Bitwise's BITB, for comparison, took in approximately $14.5 million.
The Sept. 9 outflow of $100.7 million then more than doubled the previous session's withdrawals.
Bitcoin struggles around $80,000
Meanwhile, Bitcoin slipped below the psychologically important $80,000 level earlier this week.
Investors are cautious ahead of the Federal Reserve's upcoming monetary-policy decision.
Rising Treasury yields and surging oil prices are also causing significant turbulence. Brent crude moved above $100 per barrel on Wednesday and it has obviously contributed to growing inflation concerns.
Still, the ETF data shows that institutional demand has not completely reversed, so there is some hope for the bulls.
