06212504 is referenced by 112 patents and cites 9 patents.

A method and system as presented by which valuable documents such as checks, deeds, driver's licenses, and other types of valuable documents can be imprinted with encoded symbols by a printer whereupon multiple assemblages of data can be imprinted on the valued document which is then susceptible to readout by a document reader which will automatically authenticate and verify the originator or the document and its authenticity and obviate any attempts for fraudulent alteration.

Title
Self-authentication of value documents using encoded indices
Application Number
9/226819
Publication Number
6212504 (B1)
Application Date
January 6, 1999
Publication Date
April 3, 2001
Inventor
Thomas David Hayosh
Bloomfield Hills
MI, US
Agent
Lise A Rode
US
Mark T Starr
US
Aldred W Kozak
US
Assignee
Unisys Corporation
PA, US
IPC
G06F 17/60
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