What is the primary focus when determining double patenting and restriction?

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.

When determining double patenting and restriction, the primary focus is on the claimed subject matter. As stated in MPEP 806.01:

“In passing upon questions of double patenting and restriction, it is the claimed subject matter that is considered and such claimed subject matter must be compared in order to determine the question of distinctness or independence.”

This means that examiners must carefully analyze and compare the specific claims in the patent applications to assess whether they are distinct or independent from one another.