IC card having improved security checking function

Claim 2

An IC card comprising: data storage means for prestoring a plurality of data, said plurality of data being respectively associated with a plurality of data identification codes; identification code storage means for prestoring a plurality of second identification codes which permit selective use of at least some of said plurality of data stored in said data storage means; reference information storage means for prestoring: (1) said plurality of data identification codes and (2) reference information respectively associated with each data identification code directly indicative of those second identification codes stored in said identification code storage means which are authorized to use the data respectively associated with a data identification code; and control means, responsive to the external application to said IC card of a data identification code and at least one second identification code, for selecting one or more second identification codes authorized to use data from said reference information corresponding to the applied data identification code, and determining whether or not a selected second identification code corresponds to the externally applied second identification code, and, if correspondence exists, permitting use of the data associated with the externally applied data identification code.

Claim 3

An IC card according to claim 1, wherein: said reference information storage means prestores as said reference information for each data identification code, first reference information indicating at least one second identification code and second reference information indicating at least one second identification code; and said control means permits the use of the data associated with said applied data identification code when a selected second identification code from the first reference information corresponds to the externally applied second identification code or when a selected second identification code from the second reference information corresponds to the externally applied second identification code.

Claim 4

An IC card according to claim 1, wherein said reference information associated with an externally applied data identification code defines at least one second identification code stored in said identification code storage means which must correspond to a second identification code externally applied to said IC card to permit use of the data associated with said externally applied data identification code.

Claim 5

An IC card according to claim 3 wherein said reference information defines two or more second identification code stored in said identification code storage means which must respectively correspond to two or more second identification codes externally applied to said IC card to permit use of the associated data stored in the data storage means.

Claim 6

An IC card according to claim 1 wherein use of the data stored in the data storage means includes at least one of reading the stored data and writing the stored data.

Claim 7

An IC card comprising: data storage means for prestoring a plurality of data, said plurality of data being respectively associated with a plurality of data identification codes; identification code storage means for prestoring a plurality of second identification code which permit selective use of at least some of the data stored in said data storage means; reference information storage means for prestoring: (1) said plurality of data identification codes and (2) reference information respectively associated with each data identification code directly indicative of those second identification codes stored in said identification code storage means which are authorized to use the data respectively associated with a data identification code; selecting means for selecting, when at least one second identification code is externally applied to said IC card, a corresponding second identification code stored in said identification code storage means; referencing means for referencing, when a data identification code is externally applied to said IC card, one or more second identification codes indicated in the reference information associated with said externally applied data identification code; and determining means for determining whether or not a second identification code indicated by said reference information associated with said externally applied data identification code is also selected by said selecting means and, if so, permitting use of the data.

Claim 8

An IC card comprising: data storage means for prestoring a plurality of data, said plurality of data being respectively associated with a plurality of data identification codes; identification code storage means for prestoring a plurality of second identification code which permit selective use of at least some of the data stored in said data storage means; reference information storage means for prestoring: (1) said plurality of data identification codes and (2) reference information respectively associated with each data identification code directly indicative of those second identification codes stored in said identification code storage means which are authorized to use the data respectively associated with a data identification code; selecting means for selecting, when at least one second identification code is externally applied to said IC card, a corresponding second identification code stored in said identification code storage means; referencing means for referencing, when a data identification code is externally applied to said IC card, one or more second identification codes indicated in the reference information associated with said externally applied data identification code; and determining means for determining whether or not a second identification code indicated by said reference information associated with said externally applied data identification code is also selected by said selecting means and, if so, permitting use of the data.

Claim 9

An IC card according to claim 6, wherein: said plurality of second identification codes stored in said identification code storage means include at least one terminal identification code for identifying a terminal with which said IC card can be used and at least one person identification code for identifying a person using said IC card; and said selecting means selects, when at least one terminal identification code is externally applied to said IC card, the corresponding terminal identification code stored in said identification code storage means, and selects, when at least one person identification code is externally applied to said IC card, the corresponding person identification code stored in said identification code storage means.

Claim 10

An IC card according to claim 6 wherein said reference information associated with an externally applied data identification code defines at least one second identification code stored in said identification code storage means which must correspond to a second identification code externally applied to said IC card to permit use of the data associated with said externally applied data identification code.

Claim 11

An IC card according to claim 8 wherein said reference information defines two or more second identification codes stored in said identification code storage means which must respectively correspond to two or more second identification codes externally applied to said IC card to permit use of the associated data stored in the storage means.

Claim 12

An IC card according to claim 6 wherein use of the data stored in the data storage means includes at least one of reading the stored data and writing the stored data.

Claim 15

A method according to claim 11 wherein said access information establishes a plurality of distinct correspondence conditions which must exist between one or more externally applied identification codes and one or more internally stored identification codes, and wherein access to said stored data is permitted when any one of said distinct correspondence conditions is identified in said comparing step.

Claim 16

A method according to claim 11 wherein said access includes at least one of the ability to read and write said stored data.

Claim 17

A method according to claim 11 wherein said IC card is used with an associated terminal which communicates with said IC card and wherein said terminal supplies said at least one externally applied identification code to said IC card.

Claim 18

A method according to claim 14 wherein said at least one externally applied identification code includes a plurality of externally applied identification codes, at least one being a terminal identification code and at least one being a user code.

Claim 19

A method according to claim 15 wherein said data identification code is externally applied to said IC card by said terminal in response to a transaction code which is applied to said terminal.