What is the CPC database and how does it handle patent family information?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

The CPC (Cooperative Patent Classification) database is a system that maintains technical information about patent family documents. According to MPEP 905.03(a):

“The CPC database maintains technical information regarding the patent family documents for each patent document included.”

In this database, CPC symbols are associated with patent families rather than individual documents. This means that when a document is classified, the symbol is stored as an association between the symbol and the entire patent family. As stated in the MPEP:

“When a document is classified in CPC, the symbol associated with the document is stored in the CPC database as an association between the symbol and patent family in which the document is a member.”

This approach ensures consistency across related patent documents and simplifies the classification process.