Can an inventor change what they regard as their invention during patent prosecution?

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.

Yes, an inventor or joint inventor can change what they regard as their invention during the pendency of a patent application. MPEP 2172 states:

“35 U.S.C. 112(b) or the second paragraph of pre-AIA 35 U.S.C. 112 does not prohibit the inventor or a joint inventor from changing what inventor or a joint inventor regards as the invention during the pendency of the application.”

This is supported by the case of In re Saunders, which permitted claims and submission of comparative evidence for claimed subject matter that was originally only a preferred embodiment within much broader claims. Additionally, the MPEP notes that claims in a continuation application directed to originally disclosed subject matter not initially regarded as part of the invention in the parent application can still receive the benefit of the parent application’s filing date under 35 U.S.C. 120, as established in In re Brower.