; and (ii) upon intervening— (I) be heard on all matters arising in the civil action; and (II) file petitions for appeal of a decision in the civil action. (3) Investigatory powers Nothing in this subsection may be construed to prevent the attorney general of a State from exercising the powers conferred on the attorney general by the laws of the State to conduct investigations, to administer oaths or affirmations, or to compel the attendance of witnesses or the production of documentary or other evidence. (4) Venue; service of process (A) Venue Any action brought under paragraph (1) may be brought in— (i) the district court of the United States that meets applicable requirements relating to venue under section 1391 of title 28, United States Code; or (ii) another court of competent jurisdiction. (B) Service of process In an action brought under paragraph (1), process may be served in any district in which— (i) the defendant is an inhabitant, may be found, or transacts business; or (ii) venue is proper under section 1391 of title 28, United States Code. (5) Actions by other State officials (A) In general In addition to a civil action brought by an attorney general under paragraph (1), any other officer of a State who is authorized by the State to do so may bring a civil action under paragraph (1), subject to the same requirements and limitations that apply under this subsection to civil actions brought by attorneys general. (B) Savings provision Nothing in this subsection may be construed to prohibit an authorized official of a State from initiating or continuing any proceeding in a court of the State for a violation of any civil or criminal law of the State. 4. No preemption Nothing in this Act may be construed to preempt any State law.