Internet reports that Foundry USA Pool, the most powerful bitcoin mining pool, has refunded an unintentional bitcoin transaction fee worth approximately US$777,000 (8.18 BTC). On December 19, Foundry USA Pool dug up Bitcoin block 875475, which included a transaction in which the sender added a fee of 8.18 BTC, which was 91,127 times higher than the necessary fee. On Friday, Foundry posted on social media that it had contacted the sender who had "inadvertently" paid the fee. The pool confirmed that it refunded the transaction fee to the sender after "careful consideration", otherwise the fee would have been allocated to mining customers who contributed computing power to the Foundry pool.