Patent ID: 7100045

Claim:
A computer program relating to an originality ensuring system which has a third party apparatus managing a database registering login information about said respective entity apparatuses, supplies originality ensuring digital signature of said third party apparatus to a first digital signature supplied to electronic data by a first entity apparatus, and in this way ensures originality of said electronic data for a second entity apparatus, said computer program stored in a computer-readable storage medium used for said second entity apparatus comprising: a first program code which is previously provided with login information about a transmitting first entity apparatus from said third party apparatus and then saves this login information; a second program code which receives a login request and a set of said originality ensuring digital signature, electronic data, and first digital signature from said first entity apparatus and then performs login processing based on said login information; a third program code which, upon completion of said login processing, verifies said electronic data based on said originality ensuring digital signature and said first digital signature said first entity apparatus; a fourth program code which generates an undeniable digital signature for a set of said first digital signature and second date information when said verification result is valid; a fifth program code which transmits reception confirmation including said generated undeniable digital signature to said third party apparatus; and a sixth program code which deletes said login information when said verification result is valid.