06203069 is referenced by 97 patents and cites 6 patents.

A product authentication system and method employs a unique mark that is simple and cost-effective to apply and read, but provides several layers of protection, including anti-counterfeit and anti-diversion, against counterfeiters. The unique mark includes a bar code that is printed in invisible ink comprising a UV or near-IR ink and an IR mark. The first layer of protection is invisibility. The second layer of protection is the bar code itself. The third layer of protection is the presence of the IR mark in the unique mark. The fourth layer of protection is the IR emitting characteristics of the IR mark.

Title
Label having an invisible bar code applied thereon
Application Number
9/419252
Publication Number
6203069 (B1)
Application Date
October 15, 1999
Publication Date
March 20, 2001
Inventor
Robert Loop
Westlake Village
CA, US
Chris Outwater
Santa Barbara
CA, US
Agent
Foley & Lardner
US
Assignee
DNA Technologies
CA, US
IPC
B42D 15/00
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