609.03 Applicant Has Duty to Maintain Current and Accurate Correspondence Address
The owner of an application or registration has a duty to maintain a current and accurate correspondence address. If the correspondence address changes, the USPTO must be promptly notified in writing, preferably through TEAS. See 37 C.F.R. §2.18(b)(1). This also applies to e-mail addresses, if the applicant or registrant has authorized the USPTO to send correspondence by e-mail ( see TMEP §304.03).