(i) Serving the United States and its Agencies, Corporations, Officers, or Employees.
(1) United States. To serve the United States, a party must:
(i) deliver a copy of the summons and of the complaint to the United States attorney for the district where the action is brought–or to an assistant United States attorney or clerical employee whom the United States attorney designates in a writing filed with the court clerk–or
(ii) send a copy of each by registered or certified mail to the civil-process clerk at the United States attorney’s office;
(B) send a copy of each by registered or certified mail to the Attorney General of the United States at Washington, D.C.; and
(C) if the action challenges an order of a nonparty agency or officer of the United States, send a copy of each by registered or certified mail to the agency or officer.
(2) Agency; Corporation; Officer or Employee Sued in an Official Capacity. To serve a United States agency or corporation, or a United States officer or employee sued only in an official capacity, a party must serve the United States and also send a copy of the summons and of the complaint by registered or certified mail to the agency, corporation, officer, or employee.
(3) Officer or Employee Sued Individually. To serve a United States officer or employee sued in an individual capacity for an act or omission occurring in connection with duties performed on the United States’ behalf (whether or not the officer or employee is also sued in an official capacity), a party must serve the United States and also serve the officer or employee under Rule 4(e), (f), or (g).
(4) Extending Time. The court must allow a party a reasonable time to cure its failure to:
(A) serve a person required to be served under Rule 4(i)(2), if the party has served either the United States attorney or the Attorney General of the United States; or
(B) serve the United States under Rule 4(i)(3), if the party has served the United States officer or employee.