Patent ID: 7386159

Claim:
A text document authentication method, comprising the steps of: creation a document, where said document has text thereon; creation at least a portion of the text with a combination of marking materials, including a first, visually perceptible marking material and a second, visually perceptible marking material, wherein the second visually perceptible marking material further includes a detectable, yet not visually perceptible, characteristic so as to be distinguishable from the first marking material with an aid, and the detectable characteristic is a magnetic field, and where placement of the second visually perceptible marking material is indistinguishable from the first visually perceptible marking material to the unaided eye, yet is in a predefined pattern signifying the authenticity of the document containing such a pattern, said second visually perceptible marking material is a magnetic marking material employed to print only a portion of text characters along a line of text, wherein the portion of the text characters is a vertical stroke, and where a first binary value is distinguished from a second binary value based upon the strength of the magnetic field, and reading the second marking material pattern, with the aid, so as to verify the authenticity of the document, said reading step being sensitive to the presence of the detectable characteristic of the second marking material so as to identify the predefined pattern.