Tex. Occ. Code § 601.155
A person is not required to hold a certificate issued under this chapter if the person:
Acts 1999, 76th Leg., ch. 388, Sec. 1, eff. Sept. 1, 1999.
Acts 2017, 85th Leg., R.S., Ch. 567 (S.B. 674), Sec. 9, eff. September 1, 2017.