Who bears the burden of proof in showing distinct inventions for product and process claims?

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.

In the context of a restriction requirement between product and process claims, the burden of proof initially lies with the patent examiner. According to MPEP 806.05(h):

“The burden is on the examiner to provide an example, but the example need not be documented.”

However, the burden may shift to the applicant under certain circumstances. The MPEP further states:

“If the applicant either proves or provides a convincing argument that the alternative use suggested by the examiner cannot be accomplished, the burden is on the examiner to support a viable alternative use or withdraw the requirement.”

This burden-shifting process ensures a fair examination and allows applicants to challenge the examiner’s determination if they believe it is not well-founded.