What happens if a lack of unity is found in a national stage application?

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.

If a lack of unity is found in a national stage application, the examiner will take specific actions as outlined in the MPEP 1893.03(d):

“If the examiner finds that a national stage application lacks unity of invention, the examiner may in an Office action:

• (A) Restrict the claims to one invention only,
• (B) Invite the applicant to amend the claims to eliminate the lack of unity, or
• (C) Invite the applicant to elect claims to one invention only.”

The applicant then has the option to respond by either amending the claims to overcome the lack of unity objection, electing a single invention for examination, or arguing against the lack of unity determination. If the applicant doesn’t respond adequately, the examiner may issue a final rejection on the grounds of lack of unity of invention.