Okla. Stat. tit. 59, § 59-595: Certain agreements, contracts, understandings, etc

prohibited.

No optometrist, licensed under Chapter 13 of Title 59 of the

Oklahoma Statutes, shall enter into any agreement, contract,

arrangement, practice, or understanding, written or otherwise, with

any optical supplier engaged in the sale of optical goods and

materials to the public, whereby persons are referred by the optical

supplier to said licensed person, and/or whereby persons are

referred back to the optical supplier for the purchase of optical

goods and materials.