Patent Classification Law and Legal Definition

Patent classification means organizing patent related documents such as patent applications based on the patent classification system. A patent classification is fixed under an agreement among people, and the International Patent Classification (IPC) is agreed internationally. Classification is done by patent examiners or other people who are tasked with such responsibility. Using a patent classification, one can quickly find a document disclosing the invention identical or similar to the invention for which a patent is claimed. The same document may be classified in several classes.

In the U.S., patents are classified by a system using a 3 digit class and a 3 digit subclass to describe every similar grouping of patent art. Multiple classification codes may be used to describe a single invention.