At Hillsborough County Courthouse, Florida, on Saturday, the attorney representing Graham Ivan Clark said his client owned 300 bitcoin, the Tampa Bay Times reported Sunday.
CoinDesk data shows this stash is worth $3.4 million at current market prices.
Bail was set at $725,000 during Clark's first court appearance on Saturday.
Arrested Friday, authorities see Clark as the ringleader and mastermind of July's "CryptoForHealth" Twitter hack, a coordinated attack of some 30 high profile accounts, including CoinDesk, that promised to double the money of users who sent cryptocurrency.
In total, some $117,000 worth of cryptocurrency went to the hackers in one afternoon.
Two accomplices have also been charged in California.
In an investigation last year, authorities confiscated 400 bitcoin from Clark, but later returned 300.
Although prosecutors have suggested Clark's bitcoin stash was illegally acquired, his attorney has argued it was legitimate because the authorities returned it.
Clark now stands accused on 17 counts of communications fraud, 11 counts of fraudulent use of personal information, as well as one count of breaking into an electronic device and another for organized fraud.