Tex. R. Civ. P. 621a
At any time after rendition of judgment, and so long as said judgment has not been suspended by a supersedeas bond or by order of a proper court and has not become dormant as provided by Article Section 34.001, Civil Practice and Remedies Code, the successful party may, for the purpose of obtaining information to aid in the enforcement of such judgment, initiate and maintain in the trial court in the same suit in which said judgment was rendered any discovery proceeding authorized by these rules for pre-trial matters. Also, at any time after rendition of judgment, either party may, for the purpose of obtaining information relevant to motions allowed by Texas Rule of Appellate Procedure 24 initiate and maintain in the trial court in the same suit in which said judgment was rendered any discovery proceeding authorized by these rules for pre-trial matters. The rules governing and related to such pre-trial discovery proceedings shall apply in like manner to discovery proceedings after judgment. The rights herein granted to the parties shall inure to their successors or assignees, in whole or in part. Judicial supervision of such discovery proceedings after judgment shall be the same as that provided by law or these rules for pre-trial discovery and proceedings insofar as applicable.
Tex. R. Civ. P. 621a