Thompson has been held in contempt of court since Dec. 15, 2015, and also incurred a daily fine of $1,000. In his ruling, Marbley assessed Thompson's total civil contempt fine at $3,335,000.
Thompson's case dates to his discovery of the S.S. Central America, known as the Ship of Gold, in 1988. The gold rush-era ship sank in a hurricane off South Carolina in 1857 with thousands of pounds of gold aboard, contributing to an economic panic.
Despite an investor lawsuit and a federal court order, Thompson still won't cooperate with authorities trying to find 500 coins minted from some of the gold, according to court records. He has previously said, without providing details, that the coins — valued at about $2.5 million — were turned over to a trust in Belize.
After Thompson failed to appear for a 2012 Ohio hearing to discuss the coins, U.S. marshals eventually tracked him to Florida in 2015 and arrested him. He pleaded guilty in April 2015 to skipping that hearing and was given the two-year prison sentence.
Federal law generally limits jail time for contempt of court to 18 months. But a federal appeals court in 2019 rejected Thompson’s argument that that law applies to him, saying his refusal violated conditions of a plea agreement.