Leading Ethereum mining pool Sparkpool has recently agreed to split a $330,000 ETH fee it mined earlier this year with a user who accidentally attached a 2,100 ETH fee to a transaction, leading to the huge block reward.
According to an update the firm released, shortly after mining the block with over $300,000 worth of ETH in mining fees in it, Sparkpool received an anonymous email from someone who claimed to have mistakenly attached the large fee to a transaction.
The firm asked the person to prove they were behind the transaction, by asking for a 0.022517 ETH transaction to the pool’s address, using the same address. After receiving the firms confirming the person’s identity, Sparkpool started negotiating with the sender, who was identified as someone working at a South Korean blockchain firm.
Eventually, both parties agreed Sparkpool would return half of the funds, while keeping the other half – which was then distributed to its miners, as a reward for mining the block. To confirm the deal, Sparkpool asked for a 0.666 ETH transaction, which came with a message thanking them for their integrity.
— sparkpool (@sparkpool_eth) March 11, 2019
According to available data, Sparkpool is currently the second largest Ethereum mining pool, with over 33 TH/s worth of hashrate under its belt. At the time the mysteriously large transaction fee was found, some in the cryptocurrency community speculated it was related to money laundering, or to a bug.