What is the standard for determining indefiniteness in patent claims?

The standard for determining indefiniteness in patent claims is whether those skilled in the art would understand what is claimed when the claim is read in light of the specification. As stated in the MPEP:

“A decision on whether a claim is indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph requires a determination of whether those skilled in the art would understand what is claimed when the claim is read in light of the specification.”

This standard is based on the perspective of a person of ordinary skill in the relevant art, considering the claim language, specification, and prosecution history.

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Topics: MPEP 2100 - Patentability, MPEP 2173.02 - Determining Whether Claim Language Is Definite, Patent Law, Patent Procedure
Tags: 35 Usc 112(B), Claim Interpretation, claim language, indefiniteness, patent claims