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The CPC consists of 260,000 entries and is a subdivision/extension of the IPC, an international patent classification. Visit the USPTO site on CPC.
CPC is an international standard and is used by the intellectual property offices of most developed countries.
CPC includes advanced technologies such as artificial intelligence, virtual reality, etc. within its framework. As technology changes, new codes are being added to the CPC system or branched out and integrated. As a result, each nation's intellectual property office notifies the public of newly emerging CPCs. In addition, to help you identify patents that have changed their patent classification, we provide a 'patent vs. current classification' mapping data.
Each nation's intellectual property office has granted CPCs to past patents. Therefore, you can search for past patents of each nation through CPC.
Each nation's intellectual property office mandatorily assigns one main classification CPC to each patent, and optionally assigns one or more sub classification CPCs. Typically, there are at least three to five CPCs per patent.