Cal. Ins. Code § 10232.96

When a policy or certificate holder of an insurance contract issued prior to December 31, 1996, requests a material modification to the contract as defined by federal law or regulations, the insurer, prior to approving such a request, shall provide written notice to the policy or certificate holder that the contract change requested may constitute a material modification that jeopardizes the federal tax status of the contract and appropriate tax advice should therefore be sought.