Cooperative Patent Classification

The Cooperative Patent Classification (CPC) is a patent classification system, which has been jointly developed by the European Patent Office (EPO) and the United States Patent and Trademark Office (USPTO). The CPC is substantially based on the previous European classification system (ECLA), which itself was a more specific and detailed version of the International Patent Classification (IPC) system.

Patent publications are each assigned at least one classification term indicating the subject to which the invention relates and may also be assigned further classification and indexing terms to give further details of the contents.

Each classification term consists of a symbol such as "A01B33/00" (which represents "tilling implements with rotary driven tools"). The first letter is the "section symbol" consisting of a letter from "A" ("Human Necessities") to "H" ("Electricity") or "Y" for emerging cross-sectional technologies. This is followed by a two-digit number to give a "class symbol" ("A01" represents "Agriculture; forestry; animal husbandry; trapping; fishing"). The final letter makes up the "subclass" (A01B represents "Soil working in agriculture or forestry, parts, details, or accessories of agricultural machines or implements, in general"). The subclass is then followed by a 1- to 3-digit "group" number, an oblique stroke and a number of at least two digits representing a "main group" ("00") or "subgroup". A patent examiner assigns a classification to the patent application or other document at the most detailed level which is applicable to its contents.

This classification closely follows the International Patent Classification.

An example of the CPC classification scheme in the area of agriculture is shown in the figure.

The text in curly brackets {..} refers to text provided by the CPC classification scheme. The rest of the text refers to text originating from the International Patent Classification.

The CPC scheme is accompanied by a set of CPC Definitions, which are documents which explain how to use the CPC scheme for classifying and searching a specific technology. A part of the CPC Definition related to the scheme A01B is shown in the second figure.

In the above example "A01B33/00"

Both the EPO and USPTO have been using the CPC since 1 January 2013. It replaced the ECLA system and will replace by 2015 the United States Patent Classification system (USPC) as the official patent classification scheme of both the EPO and the USPTO.

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