Mich. Comp. Laws § 752.1004b

Sec. 4b. (1) A rebate or discount from a medical supply or device manufacturer or from a company that licenses or distributes medical supplies or devices for a medical supply or device manufacturer to a consumer for that consumer's use of a medical supply or device manufactured or licensed or distributed by that manufacturer or company does not violate section 4. (2) This section does not alter any copayment, deductible, coinsurance, or other cost-sharing requirements under a contract, certificate, or policy issued by a health care corporation or health care insurer.