While cryptocurrency has been used by extremist groups and criminals to raise funds while shielding their identities, bitcoin is pseudonymous rather than anonymous. Bitcoin wallet addresses are permanent, and the digital ledger of transactions, called the blockchain, is public and can’t be changed. That means if people identify their bitcoin wallet addresses, as many right-wing groups do to raise funds, transactions can be traced, which is what allowed Chainalysis to uncover information about the source of the large December donations.