(a) It shall be unlawful for any person engaged in the sale of octane or cetane fuels in this state, in the course of such sales, either directly or indirectly:

(1) To sell product below cost; or

(2) To discriminate in price between different purchasers of product of like grade and quality, where either or any of the purchases involved in such discrimination is in commerce in this state,

and where the effect of such below-cost sale or discrimination may be substantially to lessen competition or tend to create a monopoly, or to injure, destroy, or prevent competition with any person who either grants or knowingly receives the benefit of such below-cost sale or discrimination, or with customers of either of them. Nothing contained in this Code section shall prevent differentials which make only a due allowance for differences in the cost of refining, sale, or delivery resulting from the differing methods or quantities in which such product is sold or delivered to such purchasers. Nothing contained in this Code section shall prevent persons from selecting their own customers in bona fide transactions and not in restraint of trade. Nothing contained in this Code section shall prevent price changes, from time to time, which are in response to changing conditions affecting the market for or the marketability of product of the grade and quality concerned, such as, but not limited to, imperfect or damaged product, obsolescence of product, distress sales under court process, or sales in good faith in discontinuance of business at a particular location or with respect to the product itself.

(b) Upon proof being made in any action to enforce this article that there has been a below-cost sale or discrimination, the burden of rebutting the prima-facie case thus made by showing justification shall be upon the person charged with a violation of this article. Nothing contained in this article shall prevent a seller from rebutting the prima-facie case thus made by showing that such seller's below-cost sale or lower price or the furnishing of services or facilities to any purchaser or purchasers was made in good faith to meet an equally low price of a competitor.

(c) It shall be unlawful for any person engaged in the sale of octane or cetane fuels in this state, in the course of such sales, to pay, grant, receive, or accept any thing of value as a commission or other compensation, or any allowance or discount in lieu thereof, except for services rendered in connection with the sale or purchase of product, either to the other party to such transaction or to an agent, representative, or other intermediary therein where such intermediary is acting in fact for or in behalf of or is subject to the direct or indirect control of any party to such transaction other than the person by whom such compensation is granted or paid.

(d) It shall be unlawful for any person engaged in the sale of octane or cetane fuels in this state to pay or contract for the payment of any thing of value to or for the benefit of a customer of such person in the course of such sales as compensation or in consideration for any services or facilities furnished by or through such customer in connection with the processing, handling, sale, or offering for sale of product refined, sold, or offered for sale by such person, unless such payment or consideration is available on proportionally equal terms to all other customers competing in the distribution of such product.

(e) It shall be unlawful for any person engaged in the sale of octane or cetane fuels in this state, in the course of such sales, to discriminate in favor of one purchaser against another purchaser or purchasers of product bought for resale, with or without processing, by contracting to furnish, furnishing, or contributing to the furnishing of any services or facilities connected with the processing, handling, sale, or offering for sale of such product so purchased upon terms not accorded to all purchasers on proportionally equal terms.

(f) It shall be unlawful for any person engaged in the sale of octane or cetane fuels in this state, in the course of such sales, knowingly to induce or receive a below-cost or discriminatory price which is prohibited by this article.