Okla. Stat. tit. 14A, § 14A-1-103: Supplementary general principles of law applicable

Unless displaced by the particular provisions of this act, the

Uniform Commercial Code and the principles of law and equity,

including the law relative to capacity to contract, principal and

agent, estoppel, fraud, misrepresentation, duress, coercion,

mistake, bankruptcy, or other validating or invalidating cause,

supplement its provisions.