Machine (patent) in the context of "Composition of matter"

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 series of steps for performing a function or accomplishing a result. While the terms method and process are largely interchangeable, method usually refers to a way to use a product to accomplish a given result, and process usually refers to a series of steps in manufacture. Thus, one might speak about a method for curing headaches that comprises the administration of a therapeutically effective dose of aspirin, or speak about a process for making soap or candles.

In United States patent law, an article of manufacture (also termed a manufacture) is one of the four principal categories of things that may be patented. The other three are a process (also termed a method), a machine, and a composition of matter. In United States patent law, that same terminology has been in use since the first patent act in 1790 (with the exception that processes were formerly termed "arts").

In In re Nuitjen, the United States Court of Appeals for the Federal Circuit said: