Patent ID: 8285647

Claim:
A method for maintaining privacy for transactions employing a user device having a security module and configured to communicate with an issuer computer, a privacy certification authority computer, and a verification computer, the method comprising: receiving, by the user device, a first set of attestation values from the issuer computer based on a common value unique to the security module of the user device, and further receiving the common value at the user device from the issuer computer; generating, by the user device, a first set of signature values as a function of the first set of attestation values and the common value; sending, by the user device, the first set of signature values to the privacy certification authority computer; receiving, by the user device from the privacy certification authority computer, a second set of attestation values as a function of the common value in response to the first set of signature values; generating, by the user device, a second set of signature values as a function of the second set of attestation values and the common value; sending, by the user device, the first set of signature values and the second set of signature values to the verification computer; and receiving, by the user device, access to a service, data, or information from the verification computer based on the verification computer verifying that the first set of signature values and the second set of signature values are based on the common value.