This section applies only to a pharmacy benefits manager that provides pharmacy benefits management services on behalf of a carrier. This section does not apply to reimbursement: except as provided in § 15–847.2 of this title, for specialty drugs; for mail order drugs; or to a chain pharmacy with more than 15 stores or a pharmacist who is an employee of the chain pharmacy. A pharmacy benefits manager may not reimburse a pharmacy or pharmacist for a pharmaceutical product or pharmacist service in an amount less than the amount that the pharmacy benefits manager reimburses itself or an affiliate for providing the same product or service.