David Chaum

BuilderCryptob. 1955· American

Invented blind signatures and ecash (1982) and founded DigiCash, the first working digital cash — privacy-preserving money that reveals nothing to its issuer. His Chaumian-ecash design lives on directly in modern systems like Cashu and Fedimint. Still building: the eCash 2.0 paper with the Swiss National Bank's Thomas Moser fed the BIS Project Tourbillon privacy-preserving CBDC prototype, and his xx network announced xx-coin decentralized payments and messaging in March 2026.