Classification Standards and Development

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Cooperative Patent Classification (CPC)

The Cooperative Patent Classification (CPC) effort is a joint partnership between the United States Patent and Trademark Office (USPTO) and the European Patent Office (EPO) where the Offices have agreed to harmonize their existing classification systems (European Classification (ECLA) and United States Patent Classification (USPC) respectively) and migrate towards a common classification scheme.

CPC resources:

The CPC Notice of Changes and Editorial Corrections are the official record of change for the CPC system. 

United States Patent Classification (USPC) resources

Documents and reports related to the USPC Manual of Classification

Classification Orders

A Classification Order documents changes to the USPC which have occurred while maintaining the system over time. A Classification Order identifies Reclassification Project team members, USPC classifications abolished, USPC classifications established, new classification definitions and changes to existing classification definitions.

Relationships between classifications and organizations

The Patent Technology Center Directors coordinate patent examination through Art Units.  The term, Art Unit, refers to the group of professionals responsible for a cluster of related patent art.   Art Units are currently identified by a four digit number, i.e., 1642.  

Lists of withdrawn USPTO patent publications

International classification resources

Organization and staff

Classification Standards and Development maintains the patent classification systems.

Related patent links

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