In United States patent law, a method, also called "process", is one of the four principal categories of things that may be patented through "utility patents". The other three are a machine, an article of manufacture (also termed a manufacture), and a composition of matter.
In that context, a method is a process, or series of steps or acts, for performing a function or accomplishing a result. The terms are largely interchangeable, but "process" usually refers to a manufacturing process—a series of steps for making something, while a "method" usually refers to a way of using a product to accomplish a given result. Thus, one might speak of a process for making soap or candles, or speak of a method for curing headaches comprising administering a therapeutically effective dosage of aspirin.
Not all methods, in the dictionary sense, are methods for purposes of United States patent law. The case law "forecloses a purely literal reading of § 101." The concept is elaborated in the article machine-or-transformation test.
Previously, a method patent claim could be infringed only when a single person or entity practices all claimed steps. Neither a physical device, such as a product that can be used to practice the method, nor instructions for practicing the method, are infringing until they are used by a single person to perform all the steps together. This rule was changed in Akamai Tech. v. Limelight Networks (Fed. Cir. 2012).
The European Patent Convention does not mention method patents (called process patents) so prominently, and the same applies to the TRIPS Agreement. The prime characteristic of process patents in these treaties is that "the protection conferred by the patent shall extend to the products directly obtained by such process" (Art. 64(2) EPC). Art. 28(1)(b) provides a similar rule. This shows the historical background of process patents in chemistry, where there was a need to protect new processes to manufacture known substances.
- "Types of Patents". Technology Assessment and Forecast data base. USPTO. 1 June 2000. Retrieved July 11, 2012. "Utility Patent- Issued for the invention of a new and useful process, machine, manufacture, or composition of matter, (...)"
- See Gottschalk v. Benson, 409 U.S. 63, 70 (1972) (“A process is a mode of treatment of certain materials to produce a given result. It is an act, or a series of acts, performed upon the subject-matter to be transformed and reduced to a different state or thing.”). See also In re Kollar, 286 F.3d 1326, 1332 (Fed. Cir. 2002) (“[A] process...consists of a series of acts or steps.... It consists of doing something, and therefore has to be carried out or performed.”).
- Thus section 100(b) of the US patent act, 35 U.S.C. sec. 100(b), states, "The term 'process' means process, art, or method, and includes a new use of a known process...."
- Parker v. Flook, 437 U.S. 584, 589 (1978). In Gottschalk v. Benson, 409 U.S. 63, 64 (1973), the Court said, "The question is whether the method described and claimed is a 'process' within the meaning of the Patent Act." See also In re Bilski ("But the Supreme Court has held that the meaning of 'process' as used in § 101 is narrower than its ordinary meaning.").
- "[A] method claim is only infringed when a single party can be charged with performing each step of the asserted claim." Muniauction v. Thomson Corp. and i-Deal, (Fed. Cir. 2008) opinion
- Akamai Tech. v. Limelight Networks (Fed. Cir. 2012) ipwatchdog review of decision