Okla. Stat. tit. 52, § 52-56: Oil carriers are common carriers - Discrimination

prohibited.

Every corporation, joint-stock company, partnership or person,

engaged in the business of carrying or transporting crude oil or

petroleum or any of the products thereof for hire or otherwise, by

pipeline, within this state, and by virtue of and in conformity to,

any valid law incapable of revocation by any laws of this state or

of the United States, or by virtue of and in conformity to the

provisions of this article, shall be deemed a common carrier thereof

as at common law and no such common carrier shall allow or be guilty

of any unjust or unlawful discrimination, directly or indirectly, in

favor of the carriage, transportation, storage or delivery of any

crude, stock or storage oil, or any products thereof, in its

possession or control, or in which it may be interested, directly or

indirectly.