Cal. Health & Safety Code § 1374.24

There shall be no liability on the part of, and no cause of action of any nature shall arise against, any health care service plan required to provide the notice or its authorized representatives, or agents, for any statement made, unless shown to have been made with malice in fact, by any of them in (a) any written notice or in any other oral or written communication specifying the reasons for the notice, (b) any communication providing information pertaining to that notice, or (c) evidence submitted at any court proceeding or informal inquiry in which that notice is at issue.