not as much as people may believe
..That company, Chainalysis, was the world’s first tech firm to focus solely on a task that a few years earlier might have sounded like an oxymoron: tracing cryptocurrency. The NCA was one of dozens of law enforcement agencies around the world that had learned to use Chainalysis’ software to turn the digital underworld’s preferred means of exchange into its Achilles’ heel.
Satoshi Nakamoto, the mysterious inventor of Bitcoin, had gone so far as to write that “participants can be anonymous” in an early email describing the cryptocurrency. And thousands of users of dark-web black markets like Silk Road had embraced Bitcoin as their central payment mechanism. But the counterintuitive truth about Bitcoin, the one upon which Chainalysis had built its business, was this: Every Bitcoin payment is captured in its blockchain, a permanent, unchangeable, and entirely public record of every transaction in the Bitcoin network. The blockchain ensures that coins can’t be forged or spent more than once. But it does so by making everyone in the Bitcoin economy a witness to every transaction. Every criminal payment is, in some sense, a smoking gun in broad daylight.
Within a few years of Bitcoin’s arrival, academic security researchers—and then companies like Chainalysis—began to tear gaping holes in the masks separating Bitcoin users’ addresses and their real-world identities. They could follow bitcoins on the blockchain as they moved from address to address until they reached one that could be tied to a known identity. In some cases, an investigator could learn someone’s Bitcoin addresses by transacting with them, the way an undercover narcotics agent might conduct a buy-and-bust. In other cases, they could trace a target’s coins to an account at a cryptocurrency exchange where financial regulations required users to prove their identity. A quick subpoena to the exchange from one of Chainalysis’ customers in law enforcement was then enough to strip away any illusion of Bitcoin’s anonymity.
