What is the relationship between criticality and obviousness in patent law?

Criticality plays a crucial role in rebutting obviousness rejections, particularly in cases involving ranges or amounts. According to MPEP 2144.05:

“Applicants can rebut a prima facie case of obviousness by showing the criticality of the range. ‘The law is replete with cases in which the difference between the claimed invention and the prior art is some range or other variable within the claims. . . . In such a situation, the applicant must show that the particular range is critical, generally by showing that the claimed range achieves unexpected results relative to the prior art range.'”

To establish criticality, the applicant must demonstrate that the claimed range produces unexpected results or has some other critical property that a person of ordinary skill in the art would not have expected. This often involves showing a marked improvement in some property or unexpected advantage within the claimed range.

It’s important to note that the burden is on the applicant to establish criticality: “Where the issue of criticality is involved, the applicant has the burden of establishing his position by a proper showing of the facts upon which he relies.”

To learn more:

Topics: Amounts, And Proportions, MPEP 2100 - Patentability, MPEP 2144.05 - Obviousness Of Similar And Overlapping Ranges, Patent Law, Patent Procedure
Tags: Criticality, Obviousness, patent law, Ranges, unexpected results