07239226 is referenced by 121 patents and cites 484 patents.

A transponder-reader payment system includes a fob including a transponder, and a RFID reader for interrogating the transponder. The system may further include a personalization system for populating onto the fob and RFID reader identifying information and security and authentication keys which may be used during mutual authentication of the fob and the reader and for completing a transaction. In exemplary operation, the fob and RFID reader may be personalized, the fob may be presented to the RFID reader for interrogation, the fob and reader may engage in mutual authentication, and fob identifying information may be provided to the reader for transaction completion. In another exemplary embodiment, operation of the transponder-reader payment system may be controlled by an activation circuit. Further, the fob may be responsive to multiple interrogation signals.

Title
System and method for payment using radio frequency identification in contact and contactless transactions
Application Number
10/192488
Publication Number
7239226 (B2)
Application Date
July 9, 2002
Publication Date
July 3, 2007
Inventor
John R Williamson
Jersey City
NJ, US
Sejal Ajit Shah
New York
NY, US
Kathryn D Scheding
New York
NY, US
Peter D Saunders
Salt Lake City
UT, US
Alexandra Mayers
New York
NY, US
Susan E Isenberg
New York
NY, US
Matthew C Hood
Wayne
PA, US
Jennifer Anne Elwood
New York
NY, US
David S Bonalle
New Rochelle
NY, US
Michal Bliman
Matawan
NJ, US
Michael J Berardi
Lauderhill
FL, US
Agent
Fitzpatrick Cella Harper & Scinto
Assignee
American Express Travel Related Services Company
NY, US
IPC
H04Q 1/00
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