Information processing apparatus, method therefor, computer program, and computer-readable storage medium

An electronic-data management system comprising:

• a plurality of information processing apparatuses which is connected over a network, each information processing apparatus comprising verifying means for verifying that electronic data that is shared over the network is assured as being an original and for verifying that first modification information regarding a modification of the electronic data is assured as being true;
• electronic-data modifying means for modifying the electronic data when the verifying means verifies that the electronic data is assured as being an original and the first modification information is assured as being true;
• information creating means for creating second modification information regarding a modification of the electronic data that is modified by the electronic-data modification means and for creating modification assuring information for assuring that the second modification information is true;
• and
• transmitting means for transmitting the second modification information and the modification assuring means over the network,
• wherein the plurality of information processing apparatuses cooperates with each other to manage the electronic data.

A copyright-product management system having a first information processing apparatus in the possession of an author of a primary copyright product and a plurality of second information processing apparatuses connected with the first information processing apparatus over a network, the copyright-product management system comprising:

• primary-copyright-product distributing means for distributing the primary copyright product from the first information processing apparatus to at least one of the second information processing apparatuses which is in the possession of a user that is authorized by the author, wherein the at least one second information processing apparatus makes a modification to the primary copyright product within a scope of permission granted by the author;
• transmitting means for transmitting, to the first information processing apparatus, modification information indicating content of the modification and first modification assuring information for assuring that the modification information is true, wherein the first information processing apparatus receives the modification information and the first modification assuring information and verifies whether or not the received modification information is valid using the first modification assuring information;
• and
• sending-back means for sending, when the received modification information is verified as being valid, the modification information along with second modification assuring information, which assures that the received modification information is valid, back to the at least one information processing apparatus,
• wherein the at least one information processing apparatus that has received the modification information and the second modification assuring information is granted permission to use the modified primary copyright product as a secondary copyright product.

An information processing method for processing original data created by a predetermined author, the information processing method comprising:

• an original-data verifying step of verifying that the original data is assured as being an original;
• a modification-information verifying step of verifying that modification information regarding a modification of the original data is assured as being true;
• and
• a modifying step of modifying the original data in accordance with the modification information when it is verified that the original data is assured as being an original and the modification information is assured as being true.