Larry Dean Harmon, 41, of Akron, Ohio, has been sentenced to three years in prison for running Helix, a darknet cryptocurrency mixer that facilitated over $300 million in Bitcoin transactions between 2014 and 2017.
Harmon pleaded guilty to conspiracy to commit money laundering in 2021 and has been ordered to forfeit assets exceeding $400 million, including a $311 million money judgment.
Helix, operated alongside Harmon’s darknet search engine Grams, was a go-to platform for drug dealers seeking to launder illicit funds. The mixer processed approximately 354,468 bitcoins, routing funds through darknet drug markets. Investigators linked tens of millions of dollars in illicit transactions to Helix, which had been integrated directly into major darknet platforms via APIs developed by Harmon.
In addition to his prison term, Harmon received three years of supervised release. Authorities seized cryptocurrencies, real estate, and other assets tied to the operation, and Harmon faced a $60 million civil penalty in a parallel Financial Crimes Enforcement Network action.
The case, led by IRS Criminal Investigation’s Cyber Crimes Unit and the FBI’s Cyber Division, received international support, including from Belize authorities. U.S. officials emphasized the crackdown on cryptocurrency-fueled financial crimes, underscoring the broader fight against darknet marketplaces and money laundering networks.
