What is a terminal disclaimer in patent law?

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 terminal disclaimer is a legal document filed by a patent applicant or owner to overcome a double patenting rejection. It typically:

• Disclaims the terminal part of the statutory term of a later-filed patent that would extend beyond the expiration date of an earlier-filed patent
• Agrees that the later-filed patent shall be enforceable only for and during the period that it is commonly owned with the earlier-filed patent

According to MPEP 804.02, “A terminal disclaimer filed to obviate a nonstatutory double patenting rejection is effective only with respect to the application identified in the disclaimer, unless by its terms it extends to continuing applications.”