Civil Code § 1949

Every tenant who receives notice of any proceeding to recover the real property occupied by him or her, or the possession of the real property, shall immediately inform his or her landlord of the proceeding, and also deliver to the landlord the notice, if in writing, and is responsible to the landlord for all damages which he or she may sustain by reason of any omission to inform the landlord of the notice, or to deliver it to him or her if in writing.