This came as a shock to some crypto enthusiasts, who were taken aback that such a large number of blocks in a "decentralized" and "censorship-resistant" project would reject Tornado Cash transactions. Others worried that more miners would do the same, which could eventually prevent Tornado Cash transactions from being validated at all.
The largest Ethereum miner starts blocking Tornado transactions
The Ethermine mining pool is responsible for over a quarter of all Ethereum mining, making them the largest miner for that blockchain. On August 11, three days after OFAC added the project to its sanctions list, Ethermine stopped including Tornado Cash transactions in their blocks.