Defensive Publication [Patent] Law and Legal Definition

Defensive Publication is a published patent application. It is issued by the U.S. Patent and Trademark Office (PTO) instead of a regular utility, design, or plant patent. A defensive publication is issued to an inventor who has not opted for the patent coverage. It offers only a limited protection. The protection is defensive in nature and prevents others from patenting an invention, design, or plant. Defensive Publication was made between April 1968 and May 1985. The Statutory Invention Registration replaced the U.S. defensive publication in 1985-86.

U.S. defensive publications are designated the alphabet "T" in the publication number. These publications can be searched in the PTO patent search web page.