US Finalizes Forfeiture of $400 Million Tied to Helix Darknet Mixer

U.S. authorities have finalized the forfeiture of more than $400 million in assets tied to Helix, a darknet crypto mixer used to launder proceeds from online drug markets and other criminal activities.

The government obtained legal title to the assets in question last week, following a final order entered by a federal judge on January 21.

Helix was a widely used darknet mixing service that began operations in 2014, processing up to about 354,468 Bitcoin, worth roughly $311 million at the time, according to a statement from the DOJ on Thursday.

Much of the crypto involved came from or went to “darknet drug markets,” with its operator retaining “a percentage of these transactions as his commissions and fees for operating Helix,” the DOJ wrote.

A darknet mixing service like Helix works as a tool on darknet marketplaces that obscures the origin and destination of crypto by pooling and redistributing funds, making transactions harder to trace. The term darknet refers to parts of the internet not indexed by standard search engines and are typically accessed through tools like Tor to enable anonymity.

Helix’s operator, Larry Dean Harmon, built the platform and the Grams search engine to integrate directly with major darknet markets, taking fees from transactions that investigators later traced back to “tens of millions of dollars,” per the DOJ statement.

“Helix is an example of a service built specifically to clean money from darknet markets, not a neutral privacy tool later misused, and taking it down treats that infrastructure like any other part of a criminal supply chain,” Ari Redbord, global head of policy and government affairs at TRM Labs, told Decrypt.

The DOJ’s actions feel like “removing a purpose-built laundering hub,” and doing so “forces illicit actors to abandon a trusted, integrated service and move through less direct, more exposed paths,” he said.

“It can feel like whack-a-mole, but each takedown adds real friction to the laundering process by breaking familiar routes and pushing funds into new, more traceable channels, so even when activity shifts, it becomes slower and riskier,” he added. 

The case

The U.S. government’s civil case against Harmon was based on violations of the Bank Secrecy Act tied to the service’s operation from 2014 to 2017.

Prosecutors said Harmon ran Helix as an unregistered money services business that obscured the source of Bitcoin transactions, processing more than 1.2 million transfers worth over $311 million at the time.

Court filings further allege that Harmon never registered Helix with the Financial Crimes Enforcement Network, failed to implement an anti-money laundering program, and failed to file any suspicious activity reports.

Harmon later became CEO of Coin Ninja, a registered money services business that also offered crypto exchange services and promoted a separate mixing feature.

Coin Ninja’s DropBit product allowed Bitcoin transfers via text messages or social media handles and was marketed by Harmon as a way to bypass KYC (know-your-customer) requirements, according to a separate civil case from 2022.

Authorities also noted that the service was used to move funds linked to drug sales, fraud, child exploitation, and extremist groups.

The civil action follows a criminal case in which Harmon was indicted in 2019 and pleaded guilty in 2021 to conspiring to launder money. FinCEN imposed a civil penalty in October 2020 that remains unpaid.