Document bearing characteristic ink-printed indicia juxtaposed with corresponding characteristic synthetic watermark and method for producing same

Abstract From the Canadian patent

A document security system is provided by providing each document with a synthetic watermark and within the, perimeter of at least one of the symbols which is provided by the synthetic watermark, an identical complementary or otherwise corresponding symbol is printed using ink paint, dye, stain or, similarly contrastingly pigmented substance so as to create in, combination with the synthetic watermark a juxtaposition that can be looked-for as evidence that the document is genuine and its serial number unaltered.