Data modification for magnetic cards and devices

• US 8,960,545 B1
• Filed: 11/16/2012
• Issued: 02/24/2015
• Est. Priority Date: 11/21/2011
• Status: Active Grant

• Current Assignee: Dynamics Inc.
• Original Assignee: Dynamics Inc.
• Inventors: Batra, Gautam
• Primary Examiner(s): Kim, Ahshik
• Application Number:
  US13/679,228
• Time in Patent Office: 830 Days
• Field of Search: 235/449, 235/380, 235/375
• US Class Current: 235/449
• CPC Class Codes: G06K 1/125 by magnetic means
• CPC Class Codes: G06K 19/06206 the magnetic marking being emulated
• CPC Class Codes: G06K 19/073 Special arrangements for circuits, e.g. for protecting identification code in memory protection against unauthorised use of computer memory G06F12/14

Abstract

Programming fixtures are provided that program devices, such as payment cards, with data, such as personal data, using light transmitters and receivers for powered cards, or using magnetic write heads for non-powered cards. A processor within the powered card computes a magnetic stripe message and associated longitudinal redundancy check (LRC) value based upon the personal data. The processor compares the LRC value against a list of LRC exceptions and changes the magnetic stripe message to change the LRC value based upon a positive comparison. A programming fixture may compute the magnetic stripe message and may change the magnetic stripe message before writing the magnetic stripe message to a static magnetic stripe upon a detection that the associated LRC value matches an LRC exception.

Claims

1. A method comprising:

generating a magnetic stripe message;

computing an LRC based on the magnetic stripe message;

comparing the computed LRC to a list of LRC exceptions; and

changing a data value in the magnetic stripe message based upon a positive comparison,

wherein the computed LRC changes based on the changed data value.

2. The method of claim 1, wherein the changed data value includes at least a portion of a discretionary data field within the magnetic stripe message.

3. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a payment device, the LRC based on the magnetic stripe message.

4. The method of claim 1, wherein the comparing the computed LRC to a list of LRC exceptions includes comparing, by a payment device, the computed LRC to the list of LRC exceptions.

5. The method of claim 1, wherein the changing a data value in the magnetic stripe message based upon a positive comparison includes changing, by a payment device, the data value in the magnetic stripe message based upon the positive comparison.

6. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a payment device, the LRC based on the magnetic stripe message, and

the comparing the computed LRC to a list of LRC exceptions includes comparing, by the payment device, the computed LRC to the list of LRC exceptions.

7. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a payment device, the LRC based on the magnetic stripe message, and

the changing a data value in the magnetic stripe message based upon a positive comparison includes changing, by the payment device, the data value in the magnetic stripe message based upon the positive comparison.

8. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a payment device, the LRC based on the magnetic stripe message,

the comparing the computed LRC to a list of LRC exceptions includes comparing, by the payment device, the computed LRC to the list of LRC exceptions, and

the changing a data value in the magnetic stripe message based upon a positive comparison includes changing, by the payment device, the data value in the magnetic stripe message based upon the positive comparison.

9. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a card, the LRC based on the magnetic stripe message.

10. The method of claim 1, wherein the comparing the computed LRC to a list of LRC exceptions includes comparing, by a card, the computed LRC to the list of LRC exceptions.

11. The method of claim 1, wherein the changing a data value in the magnetic stripe message based upon a positive comparison includes changing, by a card, the data value in the magnetic stripe message based upon the positive comparison.

12. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a card, the LRC based on the magnetic stripe message, and

the comparing the computed LRC to a list of LRC exceptions includes comparing, by the card, the computed LRC to the list of LRC exceptions.

13. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a card, the LRC based on the magnetic stripe message, and

the changing a data value in the magnetic stripe message based upon a positive comparison includes changing, by the card, the data value in the magnetic stripe message based upon the positive comparison.

14. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a card, the LRC based on the magnetic stripe message,

the comparing the computed LRC to a list of LRC exceptions includes comparing, by the card, the computed LRC to the list of LRC exceptions, and

the changing a data value in the magnetic stripe message based upon a positive comparison includes changing, by the card, the data value in the magnetic stripe message based upon the positive comparison.

15. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a programming system, the LRC based on the magnetic stripe message.

16. The method of claim 1, wherein the comparing the computed LRC to a list of LRC exceptions includes comparing, by a programming system, the computed LRC to the list of LRC exceptions.

17. The method of claim 1, wherein the changing a data value in the magnetic stripe message based upon a positive comparison includes changing, by a programming system, the data value in the magnetic stripe message based upon the positive comparison.

18. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a programming system, the LRC based on the magnetic stripe message, and

the comparing the computed LRC to a list of LRC exceptions includes comparing, by the programming system, the computed LRC to the list of LRC exceptions.

19. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a programming system, the LRC based on the magnetic stripe message, and

the changing a data value in the magnetic stripe message based upon a positive comparison includes changing, by the programming system, the data value in the magnetic stripe message based upon the positive comparison.

20. The method of claim 1, wherein the computing an LRC based on the magnetic stripe message includes computing, by a programming system, the LRC based on the magnetic stripe message,

the comparing the computed LRC to a list of LRC exceptions includes comparing, by the programming system, the computed LRC to the list of LRC exceptions, and

the changing a data value in the magnetic stripe message based upon a positive comparison includes changing, by the programming system, the data value in the magnetic stripe message based upon the positive comparison.