The Cooperative Patent Classification (CPC) was initiated as a joint partnership between the USPTO and the EPO ; it became the sole classification scheme for United States utility patents in January 2015.
To SEARCH for a CPC class, use the European Patent Office's Classification search
The MPEP is used extensively by patents agents/attorneys to help make sure they follow the proper USPTO regulations. The USPTO registration examination tests knowledge of the MPEP and the underlying laws and regulations.
The MPEP also provides useful guidance to members of the public on how to present persuasive arguments to a patent examiner as to why a patent should be granted on a given patent application.
The USPC classification scheme presented is primarily for historical purposes. After the implementation of the Cooperative Patent Classification (CPC), only the plant and design classification material is updated within the USPC.
The USPC is a system for organizing all U.S. patent documents and many other technical documents into relatively small collections based on common subject matter. Each subject matter division in the USPC includes a major component called a class and a minor component called a subclass. A class generally delineates one technology from another. Subclasses delineate processes, structural features, and functional features of the subject matter encompassed within the scope of a class. Every class has a unique alphanumeric identifier, as do most subclasses.
Design patents are still classified using the USPC scheme; see Design Classification for classes, definitions, and links to patents and applications.