What is the importance of demonstrating criticality of a claimed range?

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.

Demonstrating the criticality of a claimed range is crucial in overcoming obviousness rejections. The MPEP 716.02(d) provides guidance on this:

To establish unexpected results over a claimed range, applicants should compare a sufficient number of tests both inside and outside the claimed range to show the criticality of the claimed range.

This means that applicants need to provide data points within the claimed range that show unexpected results, as well as data points outside the range that don’t show these results. This helps to establish that the specific claimed range is critical to achieving the unexpected results, strengthening the argument for nonobviousness.