37 CFR §42.401

In addition to the definitions in § 42.2, the following definitions apply to proceedings under this subpart: Agreement or understanding under 35 U.S.C. 135(e) means settlement for the purposes of § 42.74. Applicant includes a reissue applicant. Application includes both an application for an original patent and an application for a reissued patent. First publication means either a patent or an application publication under 35 U.S.C. 122(b), including a publication of an international application designating the United States as provided by 35 U.S.C. 374. Petitioner means a patent applicant who petitions for a determination that another party named in an earlier-filed patent application allegedly derived a claimed invention from an inventor named in the petitioner's application and filed the earlier application without authorization. Respondent means a party other than the petitioner. Same or substantially the same means patentably indistinct.