37 CFR 1.951: Options after Office action closing prosecution in inter partes reexamination.

(a) After an Office action closing prosecution in an inter partes reexamination, the patent owner may once file comments limited to the issues raised in the Office action closing prosecution. The comments can include a proposed amendment to the claims, which amendment will be subject to the criteria of § 1.116 as to whether or not it shall be admitted. The comments must be filed within the time set for response in the Office action closing prosecution.

(b) When the patent owner does file comments, a third party requester may once file comments responsive to the patent owner's comments within 30 days from the date of service of patent owner's comments on the third party requester.