California Code, Health and Safety Code - HSC § 1358.21

(a) In recommending the purchase or replacement of any Medicare supplement coverage, an issuer or its representative shall make reasonable efforts to determine the appropriateness of a recommended purchase or replacement.

(b) Any sale of a Medicare supplement contract that will provide an individual more than one Medicare supplement policy or certificate, or contract, is prohibited.

(c) An issuer shall not issue a Medicare supplement contract to an individual enrolled in Medicare Part C unless the effective date of the coverage is after the termination date of the individual's coverage under Medicare Part C.