Editing Utility (patentability requirement) (section)

===Operability===
The importance of operability as a requirement of claims is disputed.

Janice Mueller claims that an inoperable invention may fail to satisfy the enablement requirement under 35 U.S.C. § 112 because "an inventor cannot properly describe how to use an inoperable invention...."<ref>{{cite book |first=Janice M. |last=Mueller |title=Patent Law |page=245 |edition=3rd |year=2009 |location=New York |publisher=Aspen |isbn=9780735578319 }}</ref> However, as authority Ms. Mueller's textbook cites to another textbook, Landis on Mechanics of Patent Claim Drafting, which itself cites section 2173.05(l)<ref>{{cite book |first=Robert C. |last=Faber |title=Landis on Mechanics of Patent Claim Drafting |edition=3rd |year=1990 |publisher=Practising Law Inst |isbn=9780872240070 |url-access=registration |url=https://archive.org/details/landisonmechanic00fabe }}</ref> in the [[Manual of Patent Examining Procedure]]. Section 2173.05(l) has not been part of the Manual of Patent Examining Procedure since the 1990s. The most recent pronouncement of the Manual of Patent Examining Procedure is 2107.01:

<blockquote>Situations where an invention is found to be "inoperative" and therefore lacking in utility are rare, and rejections maintained solely on this ground by a Federal court even rarer. In many of these cases, the utility asserted by the applicant was thought to be "incredible in the light of the knowledge of the art, or factually misleading" when initially considered by the Office. ... Other cases suggest that on initial evaluation, the Office considered the asserted utility to be inconsistent with known scientific principles or "speculative at best" as to whether attributes of the invention necessary to impart the asserted utility were actually present in the invention. ... However cast, the underlying finding by the court in these cases was that, based on the factual record of the case, it was clear that the invention could not and did not work as the inventor claimed it did. Indeed, the use of many labels to describe a single problem (e.g., a false assertion regarding utility) has led to some of the confusion that exists today with regard to a rejection based on the "utility" requirement.</blockquote>