It's no secret that cryptocurrency has been used for criminal activity in the past. In fact, one of the main attractions of cryptocurrency for criminals is the fact that it can be very difficult to trace the origins of the funds. This is where mixers come in. Mixers, also called tumblers, offer full anonymity for a fee by commingling cryptocurrency from different users – both legitimate and criminally-derived funds – in a manner that makes it hard to trace the origins. This is achieved by funneling different payments into a single pool before splitting up each amount and transmitting them to designated recipients, thereby turning it into an appealing option for criminals seeking to cash out and exchange the tainted money for fiat currency. According to a report from Chainalysis in January 2023, "mixers processed a total of $7.8 billion in 2022, 24% of which came from illicit addresses," and "the vast majority of illicit value processed by mixers is made up of stolen funds, the majority of which were stolen by North Korea-linked hackers." So it's no surprise that law enforcement has been cracking down on these mixer services. Most recently, a coalition of law enforcement agencies across Europe and the U.S. announced the takedown of ChipMixer, an unlicensed cryptocurrency mixer that began its operations in August 2017. "The ChipMixer software blocked the blockchain trail of the funds, making it attractive for cybercriminals looking to launder illegal proceeds from criminal activities such as drug trafficking, weapons trafficking, ransomware attacks, and payment card fraud," Europol said in a statement. The coordinated exercise, besides dismantling the clearnet and dark web websites associated with ChipMixer, also resulted in the seizure of $47.5 million in Bitcoin and 7 TB of data. This is a huge win for law enforcement in the fight against crime, but it's important to note that there are many other mixer services still in operation. So while this is a step in the right direction, there's still a long way to go.