To enable the control of rendering contents in part by using digital watermark technique:a contents serving center for embedding watermark in contents 4 embeds control information as digital watermarks within at least one of a plurality of blocks constituting electronic data by which contents are represented, thereby specifying the application of filtering to a part of the contents corresponding to the block; a contents distribution center 1 distributes the watermark-including contents to a receiving terminal 2 where checks the blocks of the received data to detect whether the control information as digital watermarks is embedded therein and applies the filtering to the block for which the embedded control information embedded has been detected in advance of reproducing the contents.