What is the difference between limiting and precedence references in CPC?
Limiting references and precedence references are both types of references found in CPC titles, but they serve slightly different purposes:
- Limiting References: As defined in MPEP 905.01(a)(1), these “exclude specific subject matter from the scope of the classification place” and are found in group titles. They help avoid overlap between classification places.
- Precedence References: These are a special type of limiting reference that, according to the MPEP, “always refers to another group or groups taking ‘precedence’ within the same subclass.” Their primary purpose is to remove overlap between two similar groups.
The main difference is that precedence references specifically establish a hierarchy between similar groups within the same subclass, while limiting references more broadly exclude subject matter from a classification place.
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