Bitcoin and Ethereum ETFs reported substantial outflows on August 21, with Bitcoin ETFs seeing a net outflow of 3,600 BTC, equivalent to $408.56 million. iShares, managed by Blackrock, accounted for 1,930 BTC of these outflows, valued at $219.04 million, while maintaining a total holding of 747,424 BTC, worth $84.81 billion. Similarly, Ethereum ETFs experienced a net outflow of 110,161 ETH, amounting to $471.49 million. iShares also led these outflows with 59,606 ETH, valued at $255.11 million, and currently holds 3,486,213 ETH, valued at $14.92 billion.