An IC card issuer issues an IC card and requests a card memory area operator to lend part of a memory area of the IC card to another card memory area user. The card memory area operator provides a memory area division apparatus and various data to the memory area division apparatus under the control of an operator communication apparatus 12. The card memory area user divides the memory area of the IC card into a memory area to be used by the IC card issuer and a memory area to be used by the card memory area user. The operation file registration apparatus writes file data for the card memory area user to the memory area of the card memory area user obtained by the above division.