A
multimedia data distributing
system comprising an ID issuing center side device and a
multimedia data
distributor side device for distributing
multimedia data as
electronic data to a purchaser of the multimedia data. The multimedia data
distributor device includes: an attribute information transmitting unit that transmits attribute information of the
electronic data indicating the multimedia data to be distributed, to the ID issuing center side device; a
watermark information embedding unit that embeds information specifying the ID number transmitted from the ID issuing center side device in response to the attribute information transmitted to the attribute information transmitting unit, as an
watermark information in the
electronic data indicating the multimedia data to be distributed; and a distribution unit that distributes the electronic data indicating the multimedia data, in which the information specifying the ID number is embedded as the
watermark information by the watermark
information embedding unit, to the purchaser of the multimedia data. The ID issuing center side device includes: an ID number
generating unit that generates a unique ID number and registering the generated ID number in a
database in a manner to correspond to the attribute information transmitted by the
distributor of the multimedia data; and an ID number transmitting unit that transmits the information specifying the generated ID number to the multimedia data distributor device.