Cal. Civ. Code § 1190

The certificate of acknowledgment of an instrument executed on behalf of an incorporated or unincorporated entity by a duly authorized person in the form specified in Section 1189 shall be prima facie evidence that the instrument is the duly authorized act of the entity named in the instrument and shall be conclusive evidence thereof in favor of any good faith purchaser, lessee, or encumbrancer. “Duly authorized person,” with respect to a domestic or foreign corporation, includes the president, vice president, secretary, and assistant secretary of the corporation.