A tag (1) can be split into a tag (A(1-a)), a tag (B(1-b)), and a tag (C (1-c)). In the tag (A), a memory portion (A31) is included. In the tag (B), a memory portion (B32) is included. In the tag (C), a memory portion (C33), an input/output interface portion (34), and a control portion (35) are provided. The input/output interface portion (34) forms an interface for exchanging data with an external reader/writer device (not shown). The control portion (35) receives a request inputted thereto from the input/output interface portion (34) and controls the function of the tag. A split line 36 is provided between the tags (A) and (B) to allow detachment between the two tags therealong. A split line 37 is provided between the tags (B) and (C) to allow detachment between the two tags therealong. The arrangement makes it difficult to falsify data in the tag and enables an easier operation.