Patent ID: 7145458

Claim:
A non-contact IC tag system comprising: a plurality of non-contact IC tags, each of which includes identification information and a memory for storing a predetermined amount of data; and a reader/writer that sends an operation command via radio to each of the non-contact IC tags, wherein the non-contact IC tags include a plurality of slave IC tags and a master IC tag, and the master IC tag holds memory configuration information that is used when building a memory space with a memory area of the memory of each of the slave IC tags and a memory area of the memory of the master IC tag wherein the reader/writer includes a memory control unit that stores identical data redundantly in at least two of the non-contact IC tags; and a readout control unit that, when data cannot be read out from a predetermined non-contact IC tag in which the data is stored by the memory control unit, controls to read out the data from other non-contact IC tag in which the data is stored redundantly.