What are the requirements for an examiner to require an applicant to add a claim to provoke an interference?

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.

An examiner may require an applicant to add a claim to provoke an interference under certain conditions. According to 37 CFR 41.202(c), the following requirements must be met:

1. The claim must be patentable to the applicant.
2. The claim must be drawn to patentable subject matter claimed by another applicant or patentee.
3. The claim must be considered apart from the question of priority under 35 U.S.C. 102(g).

The MPEP further states: Failure to satisfy the requirement within a period (not less than one month) the examiner sets will operate as a concession of priority for the subject matter of the claim.

Additionally, if the interference would be with a patent, the applicant must comply with 37 CFR 41.202(a)(2) through (a)(6), which include providing claim charts, explaining priority, and showing written description support.