08738485 is referenced by 15 patents and cites 219 patents.

Transaction processing in an offline environment for a prepaid product comprising a portable consumer device includes responding to presentation of the prepaid product at a reader for offline processing by initiating operation of the prepaid product, receiving data from the prepaid product at the reader that indicates the prepaid product is associated with a prepaid account balance, determining that the prepaid product is in a negative balance condition, and taking preventive action in response to the negative balance condition such that future acceptance of the prepaid product at a reader is prevented.

Title
Contactless prepaid product for transit fare collection
Application Number
11/966233
Publication Number
8738485 (B2)
Application Date
December 28, 2007
Publication Date
May 27, 2014
Inventor
Khalid El Awady
Mountain View
CA, US
Ayman Hammad
Pleasanton
CA, US
Philip B Dixon
San Diego
CA, US
Agent
Kilpatrick Townsend & Stockton
Assignee
Visa U
CA, US
IPC
G06Q 40/00
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