Utility (patent)
In United States patent law, utility is a patentability requirement. As provided by 35 U.S.C. § 101, an invention is "useful" if it provides some identifiable benefit and is capable of use. The majority of inventions are usually not challenged as lacking utility, but the doctrine prevents the patenting of fantastic or hypothetical devices such as perpetual motion machines.
The patent examiners guidelines require that a patent application expresses a specific, credible, and substantial utility. Rejection by an examiner usually requires documentary evidence establishing a prima facie showing that there is no specific, substantial, and credible utility.
European patent law does not consider utility as a patentability criterion. Instead, it requires that to be patentable an invention must have industrial applicability.
Utility criteria
In considering the requirement of utility for patents, there are three main factors to review: operability of the invention, a beneficial use of the invention, and practical use of the invention.