609.03 Applicant and Registrant Have Duty to Maintain Current and Accurate Correspondence Address
37 C.F.R. 2.18(c)
Maintaining and changing the correspondence addresses. The applicant, registrant, or party to a proceeding must maintain current and accurate correspondence addresses, as required by §2.23, for itself and its attorney, if one is designated. If any of these addresses change, a request to change the address, signed in accordance with § 2.193(e)(9), must be promptly filed.
37 C.F.R. 2.23(b)
Applicants, registrants, and parties to a proceeding must provide and maintain a valid email address for correspondence.
The owner of an application or registration has a duty to maintain a current and accurate correspondence address. 37 C.F.R §§2.18(c), 2.23(b). If the correspondence address changes, the USPTO must be promptly notified. See 37 C.F.R §2.18(c).