Tex. Rev. Civ. Stat. art. 8659

If any clause, sentence, paragraph, or part of this Act shall for any reason be adjudged by any court of competent jurisdiction to be invalid, such judgment shall not effect, impair, or invalidate the remainder thereof, but shall be confined in its operation to the clause, sentence, or paragraph or part thereof directly involved in the controversy in which such judgment shall have been rendered; and any contract valid under and satisfying the remaining clauses, sentences, paragraphs, or parts of this Act shall be valid and enforceable in the courts of this State.