Cal. Code of Civil Procedure § 415.95 : Jurisdiction And Service Of Process — California Code Of Civil Procedure — Service Of Summons — Manner Of Service Of Summons — Service on business organization form unknown Date: 1 Aug 2016 TEXT PDF Current through the 2016 Legislative Session (a) A summons may be served on a business organization, form unknown, by leaving a copy of the summons and complaint during usual office hours with the person who is apparently in charge of the office of that business organization, and by thereafter mailing a copy of the summons and complaint by first-class mail, postage prepaid, to the person to be served at the place where a copy of the summons and complaint was left. Service of a summons in this manner is deemed complete on the 10th day after the mailing. (b) Service of a summons pursuant to this section is not valid for a corporation with a registered agent for service of process listed with the Secretary of State. Ca. Civ. Proc. Code § 415.95 Added by Stats 2003 ch 128 (AB 418),s 2, eff. 1/1/2004.