Cal. Code of Civil Procedure § 416.10

A summons may be served on a corporation by delivering a copy of the summons and the complaint by any of the following methods: (a) To the person designated as agent for service of process as provided by any provision in Section 202, 1502, 2105, or 2107 of the Corporations Code (or Sections 3301 to 3303, inclusive, or Sections 6500 to 6504, inclusive, of the Corporations Code, as in effect on December 31, 1976, with respect to corporations to which they remain applicable). (b) To the president, chief executive officer, or other head of the corporation, a vice president, a secretary or assistant secretary, a treasurer or assistant treasurer, a controller or chief financial officer, a general manager, or a person authorized by the corporation to receive service of process. (c) If the corporation is a bank, to a cashier or assistant cashier or to a person specified in subdivision (a) or (b). (d) If authorized by any provision in Section 1701, 1702, 2110, or 2111 of the Corporations Code (or Sections 3301 to 3303, inclusive, or Sections 6500 to 6504, inclusive, of the Corporations Code, as in effect on December 31, 1976, with respect to corporations to which they remain applicable), as provided by that provision.