Tex. Health & Safety Code § 246.021
Unless a provider holds a certificate of authority issued under this subchapter, the provider may not:
Acts 1989, 71st Leg., ch. 678, Sec. 1, eff. Sept. 1, 1989.
Amended by Acts 1993, 73rd Leg., ch. 953, Sec. 2, eff. Sept. 1, 1993.