(a) In any proceeding under this subtitle, including a proceeding relating to licenses before the State Comptroller, proof of a sale by a retailer or a wholesaler of cigarettes or of any other item in combination or in connection with cigarettes at less than their cost to the retailer or their cost to the wholesaler, respectively, is prima facie evidence of intent to injure a competitor or to destroy or substantially lessen competition.
(b) In determining cost to the retailer or cost to the wholesaler, the State Comptroller or the court shall receive and consider evidence:
(1) That the person complained against purchased cigarettes at a fictitious price or on terms, in a manner, or under invoices which conceal the true costs, discounts, or terms of purchase; and
(2) Of the normal, customary, and prevailing terms and discounts in connection with other sales of a similar nature in the trade area.