(a) In general
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.

(b) Notice
The State shall serve prior written notice of any civil action under subsection (a) 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.

(c) Venue
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.

(d) Investigatory powers
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.

(e) Effect on State court proceedings
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.

(f) Limitation
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.

(g) Actions by other State officials

(1) 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 statute of such State.

(2) In addition to actions brought by an attorney general of a State under subsection (a), such an action may be brought by officers of such State who are authorized by the State to bring actions in such State for protection of consumers and who are designated by the Commission to bring an action under subsection (a) against persons that the Commission has determined have or are engaged in a pattern or practice which violates a rule of the Commission under section 5711(a) of this title.