What happens to a patent term extension application when a reissue patent is filed?

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.

When a reissue patent is filed during the processing of a patent term extension application, several steps need to be taken:

• The Office should receive notice of the reissue filing (see MPEP § 2762).
• If necessary, the applicant should request a stay of action on the term extension application (see MPEP § 2765).
• If the patent is reissued during the processing of the term extension application, the original patent no longer exists by operation of law.
• Documents and correspondence regarding the term extension application must be transferred from the original patent to the reissue patent.

As stated in MPEP § 2766: “When a patent is reissued, it is necessary to transfer the documents and correspondence regarding the application for patent term extension from the original patent into the reissue patent.“