Patent Classification System
Introduction: What is Classification?
What does classification mean for patents of trademarks.
Index to all US Patent Classes
If you do not know the class.
Search US Manual of Classification of Patents
If you know the class already.
The Office of Patent Classification
The Office of Patent Classification maintains the U.S. Patent Classification system.
International Patent Classification
The latest edition of the IPC (International Patent Classification). To go directly to seach use the link entitled "Browse and Search the Current IPC or Earlier Versions"
WIPO Guide to Using the International Patent Classification
For use with above site.
Tutorial - The British Library on Patent Classification
Patent classification schemes are used to organise and index the technical content of patent specifications so that specifications on a specific topic or in a given area of technology can be identified easily and accurately.
Manual of U.S. Patent Classification - Class Plants
List of subclasses for the plant class.
Definition of Classification For Plants PLT
PLT is the class for plants which are patentable under Title 35 U.S. Code, Section 161.