1 Tex. Admin. Code § 80.25
An unincorporated nonprofit association may appoint an individual resident of this state, a domestic or foreign corporation, whether for profit or not for profit, a business trust, estate, trust, partnership, limited liability company, association, joint venture, or any other legal or commercial entity which maintains an address in this state. A nonprofit association may not serve as its own authorized agent. Only one person may be named as the authorized agent in the statement appointing an agent for service of process. The secretary of state may not be named as the nonprofit association's authorized agent for service of process in a statement appointing an agent for service of process or any amendment to such statement.
1 Tex. Admin. Code § 80.25