What is a reissue application?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

A reissue application is a type of patent application used to correct defects in an existing, unexpired patent. According to MPEP 201.05, “A reissue application is an application for a patent to take the place of an unexpired patent that is defective.” This process allows patent holders to address errors or omissions in their original patent, ensuring that their intellectual property rights are properly protected.