Tex. Nat. Res. Code § 85.059

Each person who produces, stores, transports, refines, reclaims, treats, markets, or processes oil or gas or the products of either shall keep in this state accurate records of the amount of oil or gas which such person produced, stored, transported, refined, reclaimed, treated, marketed, or processed and of the source from which the person produced, obtained, or received the oil or gas or the products of either and the disposition made of them.