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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 scheme (The 2017.05 version of the CPC is now in force.)
- USPTO and EPO bi-lateral CPC informational site
- Statistical mapping from USPC to CPC
- CPC schemes and definitions bulk data page
- CPC concordance page
The CPC Notice of Changes and Editorial Corrections are the official record of change for the CPC system.
- CPC Notice of Changes
- CPC Notice of Editorial Corrections
- Consolidated Revision Concordance List (RCL)
- Active CPC Revision Projects
- CPC Revision Pre-releases
United States Patent Classification (USPC) resources
- Index to USPC
- Seven step strategy suggested by the Patent and Trademark Resource Center to find relevant classifications.
- USPC class numbers and titles
- Special guides to USPC and IPC: Environmentally Sound Technologies (EST) Concordance
Documents and reports related to the USPC Manual of Classification
- Classes Within the U.S. Classification System Arranged by Related Subject Matter [PDF]
- Classes Arranged in Alphabetical Order [PDF]
- Consolidated Glossary of USPC Terms
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.
- Classification Under Reclass [PDF]
- Classes in the U.S. Patent Classification System - Dates Established
- Classification Orders
- Classification Order Index (COI)
- Classification Orders Archival Report [PDF]
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.
- Classes arranged by Art Unit (CAAU)
- Classes arranged by Art Unit (CAAU) [PDF]
- Classes arranged numerically with Art Unit and search room locations (CAN)
- Classes arranged numerically with Art Unit and search room locations (CAN) [PDF]
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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