Coin mixers, which allow users to obfuscate their transactions, have been the target of law enforcement agencies across the world. ChipMixer is the latest one to face a similar crackdown.

In an operation conducted by German and US authorities, and backed by the European Union Agency for Law Enforcement Cooperation (Europol), police seized four servers, about 1909.4 Bitcoins in a series of 55 transactions (nearly $47 million), and 7 TB of data from the crypto mixing service for its alleged involvement in money laundering activities.

Other national authorities involved in the crackdown include the Cantonal Police of Zurich, Poland’s Central Cybercrime Bureau, as well as Belgium’s Federal police.

Targeting ChipMixer

According to the press release, Europol revealed that ChipMixer is an unlicensed cryptocurrency mixer set up in mid-2017, which was accessible both on the clear and in the darkweb.

The joint investigation revealed that ChipMixer allegedly carried out the laundering of 152,000 Bitcoins, a majority of which is tied to darkweb markets, ransomware groups, illicit goods trafficking, procurement of child sexual exploitation material, and stolen crypto assets.

The European law enforcement agency further stated that it was the crackdown on the Hydra Market darkweb platform that helped them uncover transactions in the equivalent of millions of euros.

ChipMixer’s service was reportedly used by prominent ransomware actors such as Zeppelin, SunCrypt, Mamba, Dharma, or Lockbit to launder ransom payments they had received.

“Authorities are also investigating the possibility that some of the crypto assets stolen after the bankruptcy of a large crypto exchange in 2022 were laundered via ChipMixer.”

Illegitimate Use of Coin Mixers

Cryptocurrency mixing platforms or tumblers essentially work by receiving digital assets from users, mixing them with other coins, and then sending the equivalent amount of “mixed” coins to a recipient address, thereby concealing the connection between the sender and recipient. ChipMixer worked in a similar way. It would turn the deposited funds into “chips,” which were then mixed together to hide all trails to where the initial funds originated.

These tumblers have legitimate use cases for the most part. However, the fact that these services have become attractive tools for cybercriminals, law enforcement has ramped up its efforts to crack down on the same.

The Office of Foreign Assets Control (OFAC) accused Tornado Cash of facilitating users to launder billions of dollars in digital assets, including $455 million allegedly stolen by notorious North Korean hacker Lazarus. The sanctions froze US assets held by Tornado Cash and prohibited companies and individuals in the country from doing business with it.