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Published July 11, 2000 | Published
Patent Open

Document copying deterrent method


The present invention is directed to a method of deterring the illicit copying of electronically published documents. It includes utilizing a computer system to electronically publish a plurality of copies of a document having electronically created material thereon for distribution to a plurality of subscribers and operating programming within the computer system so as to perform the identification code functions. The steps are to encode the plurality of copies each with a separate, unique identification code, the identification code being based on a unique arrangement of the electronically created material on each such copy; and, creating a codebook to correlate each such identification code to a particular subscriber. In some embodiments, decoding methods are included with the encoding capabilities. The unique arrangement of the electronically created material may be based on line-shift coding, word-shift coding, or feature enhancement coding (or combinations of these) and may be effected through bitmap alteration of document format file alteration.

Additional Information

Publication number US6086706. Publication type US Grant. Publication date July 11, 2000. Application number US08170619. Filing date December 20, 1993. Priority date December 20, 1993.

Attached Files

Published - US006086706.pdf


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