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1983Origins & cultureResearch & proposalsdocumented

Blind signatures make untraceable payments thinkable

David Chaum published a cryptographic method allowing a bank to sign a token without seeing what it signed.

The construction let a payer obtain a valid signature on a value the signer could not read, so a coin could be verified as genuine without being linked to the person who withdrew it. It established that electronic money did not have to choose between being verifiable and being private.