What are the criteria for distinctness between combination and subcombination inventions?

The criteria for distinctness between combination and subcombination inventions are twofold:

1. The combination as claimed does not require the particulars of the subcombination as claimed for patentability (to show novelty and unobviousness).
2. The subcombination can be shown to have utility either by itself or in another materially different combination.

Additionally, there must be reasons for insisting on restriction, such as a serious search burden or examination burden. As stated in the MPEP:

“To support a requirement for restriction between combination and subcombination inventions, both two-way distinctness and reasons for insisting on restriction are necessary, i.e., there would be a serious search burden as evidenced by separate classification, status, or field of search and/or a serious examination burden as evidenced by, for example, non-prior art issues relevant to one invention that are not relevant to the other invention.”

This guidance ensures that restriction requirements are properly justified and not arbitrarily imposed.

To learn more:

• combination
• subcombination
• distinctness
• restriction
• patent examination