When Bitcoin first appeared in 2008, one fundamental promise of the cryptocurrency was that it revealed only which coins reside at which Bitcoin addresses—long, unique strings of letters and numbers—without any identifying information about those coins’ owners. This layer of obfuscation created the impression among many early adherents that Bitcoin might be the fully anonymous internet cash long awaited by libertarian cypherpunks and crypto-anarchists: a new financial netherworld where digital briefcases full of unmarked bills could change hands across the globe in an instant.
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.