A system for visually detecting unauthorized print value, such as postal indicia on a mail piece. At least one print image is imprinted on a document based upon predetermined relationships and corresponding to a relationship indicator such that the relationship indicator is made known to an authority...http://www.google.es/patents/US6240196?utm_source=gb-gplus-sharePatente US6240196 - Mail generation system with enhanced security by use of modified print graphic information
Mail generation system with enhanced security by use of modified print ...
