What is a “single means” claim and why is it rejected under 35 U.S.C. 112(a)?

A “single means” claim is a claim that attempts to cover every conceivable means for achieving a stated function while only disclosing at most those means known to the inventor. Such claims are rejected under 35 U.S.C. 112(a) for lack of enablement.

MPEP 2166 provides a form paragraph for rejecting single means claims:

“Claim [1] rejected under 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph, because the claim purports to invoke 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, but fails to recite a combination of elements as required by that statutory provision and thus cannot rely on the specification to provide the structure, material or acts to support the claimed function. As such, the claim recites a function that has no limits and covers every conceivable means for achieving the stated function, while the specification discloses at most only those means known to the inventor. Accordingly, the disclosure is not commensurate with the scope of the claim.”

This rejection is based on the principle that a single means claim, which purports to cover all possible ways of performing a function, is not enabled by the specification, which can only disclose a limited number of ways to perform the function.

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Topics: First Paragraph, MPEP 2100 - Patentability, MPEP 2166 - Rejections Under 35 U.S.C. 112(A) Or Pre - Aia 35 U.S.C. 112, Patent Law, Patent Procedure
Tags: 35 u.s.c. 112(a), Enablement, means-plus-function, Single Means Claim