Cooperative Patent Classification (CPC)

A patent classification system developed in partnership between the USPTO and the EPO. It is an extension of the International Patent Classification (IPC) system which further classifies patent documents into specialised categories and is used by more than 45 patent offices.

More specifically, the CPC consists of:

  • all IPC symbols
  • a "main trunk" of CPC symbols, plus a Y section for tagging emerging technologies or technologies spanning several sections of the CPC
  • a 2000 series of indexing codes for additional information ("breakdown" and "orthogonal" codes)

The CPC is subject to ongoing revision by both offices, and documents are reclassified accordingly. It is designed for efficient searching, an important aspect for users of patent information.

Following the launch of the CPC International project on 24/25 August 2019, Espacenet now displays CPCI data. This means that the authorities that have assigned CPC classification symbols are now displayed next to each classification symbol.

CPC symbols will continue to be propagated at family level, which means that every member of the simple patent family will display the same CPCI symbols in the bibliographic data view.