California Code, Health and Safety Code - HSC § 1371.25

A plan, any entity contracting with a plan, and providers are each responsible for their own acts or omissions, and are not liable for the acts or omissions of, or the costs of defending, others. Any provision to the contrary in a contract with providers is void and unenforceable. Nothing in this section shall preclude a finding of liability on the part of a plan, any entity contracting with a plan, or a provider, based on the doctrines of equitable indemnity, comparative negligence, contribution, or other statutory or common law bases for liability.