Crypto exchange Bitfinex paid $23.7 million in ETH fees for transferring 100,000 USDT to a third-party wallet. The miner who included the transaction in the block and recorded it on the blockchain later returned $22.1 million to the sender's wallet.

The Block discovered an incredibly high fee transaction on the Ethereum network. Transferring 100,000 USDT from a wallet owned by the Bitfinex crypto exchange to a non-custodial exchange DeversiFi wallet cost 7676.61 ETH, which is more than $23 million at the current exchange rate.

"At 11:10 UTC on the 27th September a deposit transaction was made using a hardware wallet from the main DeversiFi user interface with an erroneously high gas fee," said a spokesperson for DeversiFi.

"DeversiFi is currently investigating the cause to determine how this occurred and will keep you updated. No customer funds on DeversiFi are at risk and this is an internal issue for DeversiFi to resolve. Operations are unaffected."

The transaction was included in a block mined by one of the largest Ethereum miners.

On average, the commission for a transaction on the Ethereum network is currently approximately $40, regardless of the transfer amount.

Later, the miner returned the overpaid commission to the Bitfinex wallet account in several tranches.

"The blockchain is immutable. But the revolution we are part of is defined by our values as humans. Thank you to the miner of block 13307440 who we can confirm is returning 7626 ETH that were incorrectly paid today as a tx fee."

Bitfinex CTO Paolo Ardoino also thanked the miner for being "proactive and fair." Ardoino also thanked the Binance crypto exchange for establishing contact with the miner.