Cal. Civ. Code § 1103.11

Any person or entity, other than a real estate licensee licensed pursuant to Part 1 (commencing with Section 10000) of Division 4 of the Business and Professions Code, acting in the capacity of an escrow agent for the transfer of real property subject to this article shall not be deemed the agent of the transferor or transferee for purposes of the disclosure requirements of this article, unless the person or entity is empowered to so act by an express written agreement to that effect. The extent of that agency shall be governed by the written agreement.