David Chaum

David Lee Chaum (born 1955) is an American computer scientist, cryptographer and inventor known as a pioneer in cryptography and privacy-preserving technologies, widely recognized as the inventor of digital cash. His 1982 dissertation is the first known proposal for a blockchain protocol, complete with code implementing all but one element of the blockchain later detailed in the Bitcoin whitepaper. He is also known for developing ecash, an electronic cash application aiming to preserve a user's anonymity, and for inventing cryptographic protocols including the blind signature, mix networks, and the Dining Cryptographers Protocol; in 1995 his company DigiCash created the first digital currency with eCash. In 2020 Chaum founded the xx network, a privacy-focused blockchain platform, and in 2021 launched xx coin, a cryptocurrency designed to enhance privacy and provide quantum resistance.