The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 03, 1998
Filed:
Aug. 10, 1995
Applicant:
Inventor:
William B Raspotnik, Longmont, CO (US);
Assignee:
HID Corporation, Irvine, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04K / ;
U.S. Cl.
CPC ...
380 24 ; 235380 ;
Abstract
An encryption method and stored value system comprising a host computer, a reader/writer that communicates with the host computer, and an RF transponder that communicates with the reader/writer. The transponder comprises a transponder chip having a memory with a plurality of memory sections, which encryption method protects data stored in the memory. The method provides a secure way to increase and decrease the value stored the transponder and to selectively write and data to and from the transponder.
Published as:
CA2182464A1; EP0758777A2; EP0758777A3; US5832090A; CA2182464C; EP0758777B1; DE69623893D1; ES2183915T3; DE69623893T2;