Tex. Utilities Code § 37.154

(a) An electric utility or municipally owned utility may sell, assign, or lease a certificate or a right obtained under a certificate if the purchaser, assignee, or lessee is already certificated by the commission to provide electric service within the same electric power region, coordinating council, independent system operator, or power pool, or if the purchaser, assignee, or lessee is an electric cooperative or municipally owned utility. As part of a transaction subject to Sections 39.262(l)-(o) and 39.915, the commission may approve a sale, assignment, or lease to an entity that has not been previously certificated if the approval will not diminish the retail rate jurisdiction of this state. Any purchase, assignment, or lease under this section requires that the commission determine that the purchaser, assignee, or lessee can provide adequate service.

(b) A sale, assignment, or lease of a certificate or a right is subject to conditions the commission prescribes.