U.S. Manual of Classification
The U.S. Manual of Classification provides a way to identify relevant patent classes and subclasses. If you already have a class or subclass in mind, you can enter it using the "class schedule" designation to see more information about the class/subclass. The Index to the U.S. Classification Index can also be helpful in determining the appropriate class and subclass. See also Patent Search Process.
Classification Definitions help to make sure you have identified the appropriate class and subclass by providing more detailed information and definitions of the classes/subclasses.
Sample Entries from the Manual of Classification Sample Entries from the Index of Classification
Sample Entries from the Manual of Classification
Sample Entries from the Index of Classification