Texas Natural Resources Code - NAT RES § 111.087. Conditions in Taking Production

(a) No common purchaser may discriminate between or against crude oil or petroleum of a similar kind or quality in favor of its own production, or production in which the common carrier may be directly or indirectly interested in whole or part.

(b) For the purpose of prorating the purchase of crude oil or petroleum to be marketed, the production shall be taken in like manner as that of any other person or producer and shall be taken in the ratable proportion that the production bears to the total production offered for market in the field.