Mark Karpeles, former CEO of the defunct bitcoin exchange Mt. Gox, will face trial this week in Tokyo on charges related to the loss of $480 million in bitcoin from the exchange. The exchange filed for bankruptcy protection in 2014 after it lost 850,000 bitcoins, according to a press release.

Mt. Gox initially claimed a bug had allowed a hacker to steal the bitcoins. However, Karpeles later claimed to have discovered 200,000 of the lost bitcoins on an offline cold wallet.

Karpeles was arrested in August 2015 on charges of embezzlement and data manipulation. The former CEO is pleading innocent to all charges.