Abstract: The present invention relates to a cryptographic protocol, and a system for implementing said protocol, for providing overt ledger secured key escrow access to encrypted data. The invention uses a plurality of trustee systems, each holding a secret share of a secret, to validate requests for the secret from authorised third parties. When a valid request is made, each trustee system publishes its secret share to a ledger. The secret shares can be combined to reveal the encryption key only by the authorised third party. Requests for the encryption key, and the responses by the trustee systems, can be accessed by the owner of the encryption key to identify the requesting third party and to have proof that the key has been revealed to the third party.