SUITS BY INJURED PERSONS OR GOVERNMENTAL ENTITIES.

(a) Suit to Recover Damages.

(1) Any person or governmental entity, including the State of Texas and any of its political subdivisions or tax-supported institutions, whose business or property has been injured by reason of any conduct declared unlawful in Subsection (a), (b), or (c) of Section 15.05 of this Act may sue any person, other than a municipal corporation, in district court in any county of this state in which any of the named defendants resides, does business, or maintains its principal office or in any county in which any of the named plaintiffs resided at the time the cause of action or any part thereof arose and shall recover actual damages sustained, interest on actual damages for the period beginning on the date of service of such person's pleading setting forth a claim under the antitrust laws and ending on the date of judgment (the rate of such interest to be in accordance with Texas law regarding postjudgment interest rates and the amount of interest to be adjusted by the court if it finds that the award of all or part of such interest is unjust in the circumstances), and the cost of suit, including a reasonable attorney's fee; provided, however, that if the trier of fact finds that the unlawful conduct was willful or flagrant, it shall increase the recovery to threefold the damages sustained and the cost of suit, including a reasonable attorney's fee; provided that interest on actual damages as specified above may not be recovered when recovered damages are increased threefold.

(2) Any person or governmental entity who obtains a judgment for damages under 15 U.S.C. Section 15 or any other provision of federal law comparable to this subsection may not recover damages in a suit under this subsection based on substantially the same conduct that was the subject of the federal suit.

(3) On a finding by the court that an action under this section was groundless and brought in bad faith or for the purpose of harassment, the court shall award to the defendant or defendants a reasonable attorney's fee, court costs, and other reasonable expenses of litigation.

(b) Suit for Injunctive Relief. Any person or governmental entity, including the State of Texas and any of its political subdivisions or tax-supported institutions, whose business or property is threatened with injury by reason of anything declared unlawful in Subsection (a), (b), or (c) of Section 15.05 of this Act may sue any person, other than a municipal corporation, in district court in any county of this state in which any of the named defendants resides, does business, or maintains its principal office or in any county in which any of the named plaintiffs resided at the time the cause of action or any part thereof arose to enjoin the unlawful practice temporarily or permanently. In any such suit, the court shall apply the same principles as those generally applied by courts of equity in suits for injunctive relief against threatened conduct that would cause injury to business or property. In any such suit in which the plaintiff substantially prevails on the merits, the plaintiff shall be entitled to recover the cost of suit, including a reasonable attorney's fee based on the fair market value of the attorney services used.

(c) Copies of Complaints to Attorney General. Any person or governmental entity filing suit under this section shall mail a copy of the complaint to the Attorney General of Texas. The attorney general as representative of the public may intervene in the action by filing a notice of intervention with the court before which the action is pending and serving copies of the notice on all parties to the action. The penalty for failure to comply with this subsection shall be a monetary fine not in excess of $200. The attorney general may file suit to recover the fine on behalf of the state in the district court in which the private suit has been brought.