United States Defensive Publication
Appearance
A United States Defensive Publication is a published patent application for which the inventor has elected not to get patent coverage. Defensive Publications were made between April 1968 and May 8, 1985. The program, called Defensive Publication Program, was replaced by the statutory invention registration program.[1]
US Defensive Publications can be searched in the United States Patent and Trademark Office's (USPTO) patent search web page.[2] They are designated by a "T" in the publication number, the letter "T" referring to "Technical disclosure".[1]