Chapter §10.02 Practical/Real-World Utility

• Jurisdiction: United States

§10.02 Practical/Real-World Utility

U.S. patent law requires that patentable inventions possess "practical utility."⁸ To be patentable an invention must have some real-world use. "Practical" use does not necessarily mean "significant" or "extensive," however. Even a chemical intermediate, which exists only for an instant of time when it is produced during the course of a chemical reaction, is useful because it is a tool that allows researchers to develop other chemicals that have useful therapeutic properties.⁹

Utility is rarely at issue for mechanical or electrical inventions; even novelty items, games, or toys that might be considered trivial or frivolous can satisfy the utility requirement. For example, the drawings from an issued utility patent directed to a hat in the shape of a fried egg are depicted in Figure 10-1. The written description of the patent affirms that the hat "finds utility, for example, as an attention-getting item in connection with promotional activities at trade shows, conventions, and the like." This is more than sufficient to satisfy the utility requirement of 35 U.S.C. §101.

FIGURE 10-1. Hat in the Shape of a Fried Egg, U.S. Patent No. 5,457,821.

Why is the utility threshold relatively low, that is, relatively easy to meet? If an invention does not offer much in the way of usefulness to society, the costs temporarily borne by the public because that invention is protected by patent will not be excessive. Inventions that are only minimally useful will most likely be made or sold in very small quantities, either by the patentee or copyists. The patentee's right to exclude all others from making, using, selling, offering to sell, and importing the claimed invention represents a minimal burden on society in this scenario.

Thus, the patent law does not attempt to evaluate the degree of utility of an invention, beyond some de minimis threshold level. Rather, the marketplace decides which inventions are the most useful, through the price the inventor can command for her patented product.¹⁰

Lack of utility is rarely raised as a basis for challenging the validity of an issued patent. Practically speaking, if the accused infringer (i.e., the challenger of validity) is producing a copy of an invention that is similar enough to spark litigation, this in itself evidences that the invention has a practical utility. Instead, utility disputes usually arise in the context of ex parte patent examination in the U.S. Patent and Trademark Office (USPTO).

As of 2019, the Federal Circuit interpreted the practical utility requirement, consistently with the Supreme Court's 1966 Brenner v. Manson decision detailed below,¹¹ as requiring that the asserted utility must be "substantial" (although the Circuit...