What are the different types of subject matter in USPC classification?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

The USPC classification system recognizes several types of subject matter. According to the MPEP, the main types are:

• Manufacture
• Art
• Apparatus
• Stock material

As stated in MPEP 903.02(b):

“The initial analysis should determine which one or ones of the several types of subject matter (manufacture, art, apparatus, or stock material) are contained in the class being considered.”

Understanding these different types of subject matter is crucial for proper classification and effective patent searching. Each type may have its own set of combinations and subcombinations within a given class.