US Patent 7983993 Authenticated payment

A buyer (110) wishes to use a payment instrument as part of an online commerce transaction with a seller (120) and it is desired to authenticate that the buyer (110) has authority to use the payment instrument. A separate authentication service (130) determines whether the buyer (110) has access to certain secret information without revealing the secret information to the seller (120). Access to the secret information would verify that the buyer (110) has authority to use the payment instrument. The authentication service (130) informs the seller (120) whether the buyer (110) is authorized to use the payment instrument.