Patentable subject matter

Overview
Section 101 of the current U.S. patent law (35 U.S.C. §101) provides that:


 * Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title.

Process, machine, manufacture, composition of matter and new and useful improvements constitute the categories of patentable subject matter. The term apparatus is used interchangeably with machine in U.S. patent law.

Excluded Subject Matter
Despite this broad mandate, courts have long held certain types of inventions unpatentable. Traditional common law exceptions include phenomena of nature, abstract intellectual concepts, mental steps, mathematical algorithms with no substantial practical application, printed matter, and, for many years, business methods.


 * The relevant principle of law "exclude[s] from . . . patent protection . . . laws of nature, natural phenomena, and abstract ideas." Diamond v. Diehr, 450 U.S. 175, 185 (1981). This principle finds its roots in both English and American law. . . . The principle means that Einstein could not have "patented his celebrated law that E=mc2; nor could Newton have patented the law of gravity." Diamond v. Chakrabarty, 447 U.S. 303, 309 (1980). Neither can one patent "a novel and useful mathematical formula." Parker v. Flook, 437 U.S. 584, 585 (1978), the motive power of electromagnetism or steam. Morse, supra, at 116, "the heat of the sun, electricity, or the qualities of metals." Funk Brothers Seed Co. v. Kalo Inoculant Co., 333 U.S. 127, 130 (1948).


 * The justification for the principle does not lie in any claim that "laws of nature" are obvious, or that their discovery is easy, or that they are not useful. To the contrary, research into such matters may be costly and time-consuming; monetary incentives may matter; and the fruits of those incentives and that research may prove of great benefit to the human race. Rather, the reason for the exclusion is that sometimes too much patent protection can impede rather than "promote the Progress of Science and useful Arts," the constitutional objective of patent and copyright protection. U.S. Const., Art. I, §8, cl. 8.


 * Patent law seeks to avoid the dangers of overprotection just as surely as it seeks to avoid the diminished incentive to invent that underprotection can threaten. One way in which patent law seeks to sail between these opposing and risky shoals is through rules that bring certain types of invention and discovery within the scope of patentability while excluding others.

Over the past twenty-five years, however, the scope of patentable subject matter has expanded significantly. For example, the Supreme Court, through two landmark decisions in 1980, held that both man-made, living organisms and computer software constitute patentable subject matter pursuant to Section 101. In 1999, the Federal Circuit ruled that business methods can be patented.