Article 9 of the UCC makes ineffective any term in a contract prohibiting the assignment of a security interest arising out of a sale of any right to payment for goods sold.

Article 9 of the UCC (Uniform Commercial Code) is designed to regulate secured transactions, including the assignment of security interests. It generally invalidates clauses in contracts that prohibit the assignment of a security interest in accounts, general intangibles, or payment intangibles, which includes rights to payment for goods sold. This is to facilitate the free flow of commerce by allowing businesses to use their accounts receivable as collateral.