Patent ID: 7020636

Claim:
A storage-medium rental system for temporarily providing a right to use digital work to a user from a rental agent, said storage-medium rental system comprising: a portable storage medium for storing the digital work thereon, and for prestoring content information representing the digital work; a portable semiconductor memory having an area for securely storing information; a rental-shop apparatus operable to securely write right information, which indicates a range of a right to use the digital work stored on said portable storage medium, into said area of said portable semiconductor memory when the rental agent rents said portable storage medium to the user; and a reproduction apparatus operable to, upon receiving an instruction from the user to reproduce the digital work stored on said portable storage medium, securely read the right information from said area of said portable semiconductor memory, judge whether the digital work is allowed to be used or not by the user based on the read right information, and read the content information from said portable storage medium and reproduce the digital work based on the read content information only when judging that the digital work is allowed to be used; wherein said portable conductor memory is connected to said rental-shop apparatus when the rental agent rents said portable storage medium to the user, and said portable storage medium and said portable semiconductor memory are connected to said reproduction apparatus when the user reproduces the digital work; wherein the user makes a rental payment to the rental agent when the rental agent rents said portable storage medium to the user, and said rental-shop apparatus is operable to securely write the right information into said area of said portable semiconductor memory when the rental agent receives the rental payment from the user; and wherein said portable storage medium is operable to store first identification information, which identifies the digital work, in correspondence with the content information, said rental-shop apparatus is operable to write the right information including second identification information, which identifies the digital work, into said area of said portable semiconductor memory, and said reproduction apparatus is operable to compare the first identification information stored in said portable storage medium and the second identification information included in the read right information, and to judge that the digital work identified by the content information stored in correspondence with the first identification information is allowed to be used only when the first identification information and the second identification information match.