What does the MPEP say about using the term “about” in patent claims?

The MPEP addresses the use of the term “about” in patent claims in MPEP 2173.05(b). The term is considered a relative term that must be interpreted in the context of the claim and specification. The MPEP states:

“The term ‘about’ avoids a strict numerical boundary to the specified parameter. See Ortho-McNeil Pharmaceutical, Inc. v. Caraco Pharmaceutical Laboratories, Ltd., 476 F.3d 1321, 1326, 81 USPQ2d 1427, 1432 (Fed. Cir. 2007).”

Whether the use of “about” is acceptable depends on whether the specification provides some standard for measuring that degree. If a person of ordinary skill in the art can determine the scope of the invention with reasonable certainty, the term may be definite enough. However, if the term’s boundaries are unclear, it could render the claim indefinite.

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Topics: MPEP 2100 - Patentability, MPEP 2173.05(B) - Relative Terminology, Patent Law, Patent Procedure
Tags: About, claim language, indefiniteness, Relative Terms