Can double patenting rejections be made in ex parte reexamination?

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.

Yes, double patenting rejections can be made in ex parte reexamination, but with specific conditions:

• Double patenting rejections are permitted if they are based on patents or printed publications.
• These rejections must raise a substantial new question of patentability.
• The MPEP 2258 states: “Double patenting rejections may be made in reexamination proceedings, including reexamination proceedings ordered on or after November 2, 2002.”

However, it’s important to note that the scope of double patenting rejections in reexamination is limited compared to original examination. The focus remains on issues arising from prior art patents or printed publications.