In the desired number of reproductions 74, a value which is desired to be set as a permitted number of reproductions of the LT 80 a to be acquired is stored. [0125] The LT return unit 305 a as shown in FIG. 8 is a means for returning the LT 80 a to the right management server 20 a by generating the LT return request 90 a and sending it to the right management server 20 a. [0126]FIG. 10 is a diagra