Whenever an attorney general of any State has reason to believe that the interests of the residents of that State have been or are being threatened or adversely affected because any person has engaged or is engaging in a pattern or practice which violates any rule of the Commission under section 5711(a) of this title, the State may bring a civil action on behalf of its residents in an appropriate district court of the United States to enjoin such pattern or practice, to enforce compliance with such rule of the Commission, to obtain damages on behalf of their residents, or to obtain such further and other relief as the court may deem appropriate.
The State shall serve prior written notice of any civil action under subsection (a) of this section upon the Commission and provide the Commission with a copy of its complaint, except that if it is not feasible for the State to provide such prior notice, the State shall serve such notice immediately upon instituting such action. Upon receiving a notice respecting a civil action, the Commission shall have the right (1) to intervene in such action, (2) upon so intervening, to be heard on all matters arising therein, and (3) to file petitions for appeal.
Any civil action brought under this section in a district court of the United States may be brought in the district wherein the defendant is found or is an inhabitant or transacts business or wherein the violation occurred or is occurring, and process in such cases may be served in any district in which the defendant is an inhabitant or wherever the defendant may be found.
For purposes of bringing any civil action under this section, nothing in this chapter shall prevent the attorney general from exercising the powers conferred on the attorney general by the laws of such State to conduct investigations or to administer oaths or affirmations or to compel the attendance of witnesses or the production of documentary and other evidence.
Nothing contained in this section shall prohibit an authorized State official from proceeding in State court on the basis of an alleged violation of any general civil or criminal antifraud statute of such State.
Whenever the Commission has instituted a civil action for violation of any rule or regulation under this chapter, no State may, during the pendency of such action instituted by the Commission, subsequently institute a civil action against any defendant named in the Commission's complaint for violation of any rule as alleged in the Commission's complaint.