Texas Natural Resources Code - NAT RES § 111.086. Discrimination Between Persons and Fields

(a) A common purchaser shall purchase oil offered to it for purchase without discrimination in favor of one producer or person against another producer or person in the same field and without unjust or unreasonable discrimination between fields in this state.

(b) A question of justice or reasonableness under this section shall be determined by the commission taking into consideration the production and age of wells in respective fields and all other proper factors.