What is considered when determining if a substantial new question of patentability exists?

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.

The determination of whether a substantial new question of patentability exists is based on the patent claims in effect at the time of the determination. The MPEP states:

“The patent claims in effect at the time of the determination will be the basis for deciding whether a substantial new question of patentability has been raised.” (37 CFR 1.515(a))

It’s important to note that amendments presented with the request (if filed by the patent owner), filed in a pending reexamination proceeding, or submitted in a reissue application where no reissue patent has been issued, will not be considered when deciding on the request.

Additionally, the determination does not involve making a decision on patentability/unpatentability of the claims. The focus is solely on whether a substantial new question of patentability is raised by the request and the prior art cited therein.