An American cryptocurrency researcher was sentenced to 63 months in prison and fined $100,000 for helping North Korea evade sanctions, a federal judge ruled on Tuesday, marking the latest courtroom victory for U.S. sanctions against Pyongyang.

Virgil Griffith, who formerly headed up the Ethereum Foundation, attended a cryptocurrency conference in Pyongyang in April 2019. Organizers for the event explicitly asked Griffith to stress the “potential money laundering and sanction evasion applications” of cryptocurrency and blockchain technology, according to government prosecutors.