What is the general procedure for identifying appropriate CPC groups for 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 general procedure for identifying appropriate CPC groups for classification involves two main steps:

1. Identify appropriate subclasses covering the subject matter to be classified:
• Review subclass titles for scope coverage
• Consult subclass notes, references, and definitions to verify scope
• Repeat until a suitable subclass is found
2. Identify appropriate group(s) within the subclass:
• Identify candidate main groups
• Verify notes, references, and definitions don’t exclude the subject matter
• Consider special rules like Multiple Aspect classification or Indexing
• Follow precedence notes and limiting references
• Consider application/functional classification places
• Identify genus/species classification places
• Use residual classification places if necessary

As stated in MPEP 905.03(b): “The general procedure for identifying the appropriate groups for covering the subject matter to be classified is as follows: (A) Identify the appropriate subclasses covering the subject matter to be classified. […] (B) Identify the appropriate group(s) covering the subject matter to be classified.”