(a) Any person who is injured by any act taken or permitted in violation of this chapter may, on behalf of the person and others similarly situated, maintain an action in a district court in Travis County, regardless of the amount in controversy, for temporary or permanent injunctive relief, declaratory relief, or other relief, including damages, such action to be pursued in accordance with Rule 42, Texas Rules of Civil Procedure.
(b) A party filing such an action must give prompt notice to the attorney general, who shall be permitted to join, on application within 30 days, as a party plaintiff.