Patent ID: 7540421

Claim:
A method of monitoring the distribution of articles comprising the steps of: (a) creating a series unique labels by printing a succession of unique composite indicium on a substrate, said labels useful for labeling each article in a series of articles and formed by feeding said substrate having a first location and successive locations through a printing apparatus that prints a first indicium having a first pattern at said first location and at said successive distinct locations on said substrate, feeding said substrate through an apparatus that prints a second indicium at said first location and at each said successive location, the combination of said first indicium and said second indicium at said first location and each said successive location comprising a unique composite indicium for each label, at least one of said first and second indicium being unchanged with each successive label printing, and the other indicium being displaced relative to the first printed indicium for each successive label to form said series of unique composite indicium; (b) labeling successive articles with successive labels having a unique composite indicium; (c) scanning each said unique composite indicium label on the articles; (d) using an algorithm to derive a unique character string corresponding to each said unique composite indicium; and (e) storing the character string in a storage means to maintain data associated with the article.