Is double inclusion always improper in patent claims?

No, double inclusion is not always improper in patent claims. The MPEP 2173.05(o) clearly states:

“There is no per se rule that ‘double inclusion’ is improper in a claim.”

The MPEP further elaborates by citing In re Kelly, which states:

“Automatic reliance upon a ‘rule against double inclusion’ will lead to as many unreasonable interpretations as will automatic reliance upon a ‘rule allowing double inclusion’. The governing consideration is not double inclusion, but rather is what is a reasonable construction of the language of the claims.”

This means that each case of double inclusion should be evaluated on its own merits, considering whether it leads to indefiniteness or uncertainty in the claim’s scope.

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Topics: MPEP 2100 - Patentability, MPEP 2173.05(O) - Double Inclusion, Patent Law, Patent Procedure
Tags: Claim Construction, claim drafting, Double Inclusion, In Re Kelly, patent claims