The state of the art is the highest level of development, as of a device, technique, or scientific field, achieved at a particular time.

Usage note

The phrase "state of the art" should be hyphenated when it is used as an adjective, e.g.: "This machine is an example of state-of-the-art technology", but not when used as a noun, as in the paragraph above.

Patent law

In the context of the European patent law, the term "state of the art" is a very important concept in the process of assessing novelty and inventive step, and is a synonym of the expression "prior art" [1] [2]. "The state of the art shall be held to comprise everything made available to the public by means of a written or oral description, by use, or in any other way, before the date of filing of the European patent application" according to Art 54(2) EPC [3]. Due account should be taken of Art. 54(3) as well, but merely for the examination of novelty.

The expression "background art" is also used in certain legal provisions, such as Rule 27, and has the same meaning [4]. The expression "internal state of the art" is used to describe the state of the art merely on possession of the (patent) applicant, but not in the public domain.