Patent ID: 7389272

Claim:
A method of generating license information related to digital contents of information comprising: receiving a purchase request from a user, the request including an identification of digital contents information, a utilization condition of the digital contents information, and a media identification of a media to which the user records the digital contents information, the digital contents information comprising officially copied contents information which is copied under a right for selling the contents information and privately copied contents information which is copied without a right for selling the contents information, and the utilization condition information of the privately copied contents information being more restricted than the utilization condition information of the officially copied contents information; determining a content key for the digital contents information based on the identification; generating a certificator based on the content key and the utilization condition; generating a license key based on the media identification; encrypting the content key, the utilization condition, and the certificator based on the license key; generating a digital signature of encrypted content key, encrypted utilization condition, and encrypted certificator based on a secret key; and generating a digital license information including a header, the encrypted content key, the encrypted utilization condition, the encrypted certificator, and the digital signature.