Texas Business and Commerce Code - BUS & COM § 71.201. Civil Action;  Sanction

(a) A person's failure to comply with this chapter does not impair the validity of any contract or act by the person or prevent the person from defending any action or proceeding in any court of this state, but the person may not maintain in a court of this state an action or proceeding arising out of a contract or act in which an assumed name was used until an original, new, or renewed certificate has been filed as required by this chapter.

(b) In an action or proceeding brought against a person who has not complied with this chapter, the court may award the plaintiff or other party bringing the action or proceeding expenses incurred, including attorney's fees, in locating and effecting service of process on the defendant.