Okla. Stat. tit. 15 § 566
Every person shall furnish upon demand to any principal for whom such person has executed any contract of sale for the future delivery of any cotton, grain, stocks or other commodities a written instrument setting forth the name and location of the exchange, board of trade or similar institution upon which such contract has been executed, the date of execution of the contract and the name and address of the persons with whom such contract was executed and if such person shall refuse or neglect to furnish such statement upon reasonable demand, such refusal or neglect shall be prima facie evidence that such contract was an illegal contract within the provisions of Section 4, of this act, and that the person who executed it was engaged in the maintenance and operation of a "bucket shop" within the provisions of Section 7, of this act.
Okla. Stat. tit. 15, § 566