Office of Patent Classification
The Office of Patent Classification maintains the patent classification systems.
Organization and Staff
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.
I don’t know anything about CPC. Where do I start?
- Use the USPTO and EPO bi-lateral Cooperative Patent Classification (CPC) informational site on WWW
- Start browsing the CPC scheme on www.uspto.gov
I know a USPC classification and I want to find a relevant CPC. What do I do?
- Use the Classification Search Page to look up a Statistical Mapping from USPC to CPC.
I know a CPC group symbol (e.g., B02C 19/0081) and I want to see the group title, browse the scheme or read its definition. How do I do this?
- Use the Classification Search Page to look up a CPC Scheme or Definition by CPC Symbol
I want to download CPC scheme and definition source files (e.g., XML, PDF); and CPC to IPC concordance files. How do I do this?
- Use the CPC Deliverables page on the Cooperative Patent Classification bi-lateral Web site to download this information.
United States Patent Classification (USPC) Resources
I don’t know anything about USPC. Where do I start?
- Use the Index to USPC to browse an alphabetical listing of concepts and access relevant USPC classification schedules.
- Use the Seven Step Strategy suggested by the Patent and Trademark Resource Center to find relevant classifications.
- Special guides to USPC and IPC
- Browse a listing of USPC Class numbers and titles
- Consolidated Glossary of USPC Terms used in USPC definitions
- Additional guides
I know a USPC classification symbol (e.g., Class 345 or Class/Subclass 345/418) and I want to:
- browse the USPC classification schedule or USPC classification definition
- Use the Classification Search Page to look up a USPC schedule or definition by USPC symbol
- Use the Classification Search Page to look up a USPC schedule or definition by USPC symbol
- find a relevant CPC
- Look up a Statistical Mapping from USPC to CPC by using the Classification Search Page to, or
- find a relevant International Patent Classification (IPC)
- Look up a Mapping from USPC to IPC by using the Classification Search Page
- USPC-to-IPC Reverse Concordance
Documents and Reports Related to the USPC Manual of Classification
- Classes Within the U.S. Classification System (Arranged by Related Subjects) [PDF]
- Classes Arranged in Alphabetical Order [PDF]
- Consolidated Glossary of USPC Terms
I want to understand more about how USPC has changed over time
A Classification Order documents changes to the UPSC 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
- Use the Classification Orders
- Classification Order Index (COI)
- Classification Orders Archival Report [PDF]
Relationships between classifications and organizations
- Classes Arranged by Art Unit (CAAU)
- Classes Arranged Numerically With Art Unit and Search Room Locations (CAN)
Lists of withdrawn USPTO Patent Publications
International Classification Resources
Related Patent Links
Some contents linked to on this page require a plug-in for PDF files .
The Inventors Assistance Center is available to help you on patent matters. Send questions about USPTO programs and services to the USPTO Contact Center (UCC) . You can suggest USPTO webpages or material you would like featured on this section by E-mail to the webmaster@uspto.gov . While we cannot promise to accommodate all requests, your suggestions will be considered and may lead to other improvements on the website.