Cal. FIN § 16007

(a) Not less than 30 days before a foreign (other state) credit union establishes a California branch office or a California facility, the foreign (other state) credit union shall file with the commissioner, in the form that the commissioner may by regulation or order require, an appointment irrevocably appointing the commissioner and the commissioner’s successor from time to time in office to be the foreign (other state) credit union’s attorney to receive service of any lawful process in any noncriminal judicial or administrative proceeding against the foreign (other state) credit union or any of its successors that arises out of the activities of the California branch office or California facility after the appointment has been filed, with the same force and validity as if served personally on the foreign (other state) credit union or its successors, as the case may be.

(b) Any foreign (other state) credit union that maintains a California branch office or California facility that has not filed with the commissioner an appointment pursuant to subdivision (a) is deemed by the maintenance of the branch office or facility to have appointed the commissioner as its attorney to receive service of any lawful process in any noncriminal judicial or administrative proceeding against the foreign (other state) credit union or any of its successors that arises out of the activities of the California branch office or California facility, with the same force and validity as if served personally on the credit union or its successor, as the case may be.

(c) Service may be made on a foreign (other state) credit union that has appointed or is deemed to have appointed the commissioner as its attorney for service of process by leaving a copy of the process at any office of the commissioner. However, the service is not effective unless (1) the party making the service, who may be the commissioner, forthwith sends notice of the service and a copy of the process by registered or certified mail to the foreign (other state) credit union served at the last address on file with the commissioner for any of the foreign (other state) credit union’s offices in this state or at its head office, and (2) an affidavit of compliance with this subdivision by the party making the service is filed in the case on or before the return date if any, or within any further time that the court, in the case of a judicial proceeding, or the administrative agency, in the case of an administrative proceeding, allows.