05671282 is referenced by 331 patents and cites 11 patents.

A document processing system in which a server subsystem stores information corresponding to a document containing human readable and machine readable information and a client subsystem receives the document and interprets the machine readable information. The client subsystem contacts the server to verify validity of information in the document using a communications network that allows information to be exchanged between the server and the client.

Title
Method and apparatus for document verification and tracking
Application Number
8/376861
Publication Number
5671282
Application Date
January 23, 1995
Publication Date
September 23, 1997
Inventor
K Venkatesh Prasad
Cupertino
CA, US
David G Stork
Stanford
CA, US
Gregory J Wolff
Mountain View
CA, US
Agent
Blakely Sokoloff Taylor & Zafman
Assignee
Ricoh Company
JP
Ricoh Corporation
CA, US
IPC
H04L 9/00
View Original Source