37 CFR § 1.497 - Inventor's oath or declaration under 35 U.S.C. 371(c)(4).
(a) When an applicant of an international application desires to enter the national stage under 35 U.S.C. 371 pursuant to § 1.495, and a declaration in compliance with § 1.63 has not been previously submitted in the international application under PCT Rule 4.17(iv) within the time limits provided for in PCT Rule 26ter.1, the applicant must file the inventor's oath or declaration. The inventor, or each individual who is a joint inventor of a claimed invention, in an application for patent must execute an oath or declaration in accordance with the conditions and requirements of § 1.63, except as provided for in § 1.64.
(b) An oath or declaration under § 1.63 will be accepted as complying with 35 U.S.C. 371(c)(4) if it complies with the requirements of §§ 1.63(a), (c) and (g). A substitute statement under § 1.64 will be accepted as complying with 35 U.S.C. 371(c)(4) if it complies with the requirements of §§ 1.64(b)(1), (c) and (e) and identifies the person executing the substitute statement. If a newly executed inventor's oath or declaration under § 1.63 or substitute statement under § 1.64 is not required pursuant to § 1.63(d), submission of the copy of the previously executed oath, declaration, or substitute statement under § 1.63(d)(1) is required to comply with 35 U.S.C. 371(c)(4).
(c) If an oath or declaration under § 1.63, or substitute statement under § 1.64, meeting the requirements of § 1.497(b) does not also meet the requirements of § 1.63 or § 1.64, an oath, declaration, substitute statement, or application data sheet in accordance with § 1.76 to comply with § 1.63 or § 1.64 will be required.