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EP0212615A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

IC card

Assignee: Casio Computer Co Ltd
•
Filing: 1986-08-18
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Granted: —
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Expires: 2006-08-18
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Abstract

Abstract When identification data stored in a predetermined area of a data memory (65) in an IC card (11) and data supplied from a card terminal coincide, the data stored in the data memory (65) is substantially erased.

Inventors

  • 👤 Shigeyuki Pat. Dpt. D. Div. Hamura R & D Kawana
  • 👤 Harumi Pat. Dpt. D. Div. Hamura R & D Nakano

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-29 19:07
CPC Classifications
G; G07; G07F; G07F7/00; G07F7/08; G07F7/10; G07F7/1008; G06; G06Q; G06Q20/00; G06Q20/30; G06Q20/34; G06Q20/341; G06Q20/355; G06Q20/3558; G06Q20/357

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 79 words
An IC card characterized by comprising: memory means (65) having at least one memory area for storing secret data therein; means (58) for reading out data stored in said memory means; first comparator means (63) for checking whether externally supplied data and data read out by said reading means are coincident; and means (56) for substantially erasing said secret data stored in said memory means (65) when the coin­cidence of data compared in said first comparator means is detected.
Claim 2
Dependent Claim 79 words
An IC card characterized by comprising: memory means (65) having at least one memory area for storing secret data therein; means (58) for reading out data stored in said memory means; first comparator means (63) for checking whether externally supplied data and data read out by said reading means are coincident; and means (56) for substantially erasing said secret data stored in said memory means (65) when the coin­cidence of data compared in said first comparator means is detected.
Claim 3
Dependent Claim 33 words
An IC card according to claim 1, characterized in that the secret data stored in said memory means (65) is information data for checking the validity of at least one IC card holder.
Claim 4
Dependent Claim 50 words
An IC card according to claim 2, characterized in that said identification data is production master key (PMK) data for checking the validity of an IC card holder in the manufacturing of an IC card (11), and said PMK data is deleted upon completion of delete IC card manufacturing stage.
Claim 5
Dependent Claim 54 words
An IC card according to claim 3, characterized in that said identification data is initialization per­sonal identification number (IPIN) data for checking the validity of an IC card holder in an IC card issuing of an IC card (11), and said IPIN data is deleted upon com­pletion of a regular IC card issuing stage.
Claim 6
Dependent Claim 50 words
An IC card according to claim 1, characterized in that each said memory area of said memory means (65) has a flag area for storing flag data, said flag data representing that corresponding secret data can not be used, said secret data being deleted in effect by said flag data.
Claim 7
Dependent Claim 95 words
An IC card according to claim 1, which further comprises: calculating means (56b) for calculating check sum data of data to be written in said memory means (65); means for writing said check sum data calculated by said calculating means together with said data in said memory means; and second comparator means (68) for comparing check sum data calculated by said calculating means before writing of data in said memory means and check sum data stored in said memory means, thereby effecting a check as to whether data is correctly written in said memory means.
Claim 8
Dependent Claim 42 words
An IC card according to claim 6, which further comprises: means (62) for providing a signal representing abnormality of said memory means to the outside of said IC card when non-coincidence of data compared by said second comparator means (68) is detected.
Claim 9
Dependent Claim 32 words
An IC card according to claim 1, characterized in that said secret data stored in said memory means (65) is supplied from a card terminal on which said IC card is attached.

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