Okla. Stat. tit. 24, § 24-122: Supplementary principles of law and equity

Unless displaced by the provisions of the Uniform Fraudulent

Transfer Act, the principles of law and equity, including the law

merchant and the law relating to principal and agent, estoppel,

laches, fraud, misrepresentation, duress, coercion, mistake,

insolvency, or other validating or invalidating cause, supplement

the provisions of the Uniform Fraudulent Transfer Act.