What are the key criteria for establishing distinctness in subcombinations usable together?

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 key criteria for establishing distinctness in subcombinations usable together are:

• The subcombinations must have separate utility
• The inventions must be shown to be separately usable
• There must be evidence of separate status in the art
• There must be evidence of different classification

According to MPEP 806.05(d), “To support a requirement for restriction between subcombinations usable together, both two-way distinctness and reasons for insisting on restriction are necessary.” The MPEP further states, “The inventions are distinct if they do not overlap in scope and are not obvious variants, and if it is shown that at least one subcombination is separately usable.”