Texas Business and Commerce Code - BUS & COM § 610.002. Unauthorized Categorization of Certain Transactions

(a) A person or entity involved in facilitating or processing an electronic payment transaction, including a payment card issuer or payment card network, may not assign to a merchant or require a merchant to use a firearms code.

(b) For the purposes of the sale of firearms, ammunition for use in firearms, and firearms accessories, a firearms retailer may not provide a firearms code to a payment card issuer or payment card network and may only use or be assigned a merchant category code for general merchandise retailers or sporting goods retailers. Any agreement or contractual provision to the contrary is void.

(c) A payment card issuer or payment card network shall notify the payment card holder in writing on every occasion that a firearms code is assigned to an electronic payment transaction on the payment card holder's account.