Tex. Fin. Code § 345.302

Notice to a retail buyer of an assignment or negotiation of a retail installment contract or retail charge agreement or an outstanding balance under a contract or agreement or a requirement that the retail seller be deprived of dominion over payments on a contract or agreement or over the goods if returned to or repossessed by the seller is not necessary for a written assignment or negotiation of the contract or agreement or an outstanding balance under the contract or agreement to be valid as against a creditor, subsequent purchaser, pledgee, mortgagee, or lien claimant of the seller.