Section 5C. (1) The attorney general shall investigate violations under sections 5B to 5O, inclusive, involving state funds or funds from any political subdivision. If the attorney general finds that a person has violated or is violating said sections 5B to 5O, inclusive, the attorney general may bring a civil action in superior court against the person.

(2) An individual, hereafter referred to as relator, may bring a civil action in superior court for a violation of said sections 5B to 5O, inclusive, on behalf of the relator and the commonwealth or any political subdivision thereof. The action shall be brought in the name of the commonwealth or the political subdivision thereof. The action may be dismissed only if the attorney general gives written reasons for consenting to the dismissal and the court approves the dismissal. Notwithstanding any general or special law to the contrary, it shall not be a cause for dismissal or a basis for a defense that the relator could have brought another action based on the same or similar facts under any other law or administrative proceeding.

(3) When a relator brings an action under said sections 5B to 5O, inclusive, a copy of the complaint and written disclosure of substantially all material evidence and information the relator possesses shall be served on the attorney general pursuant to Rule 4(d) (3) of the Massachusetts Rules of Civil Procedure. The complaint shall be filed under seal and shall remain so for 120 days after service upon the attorney general. Notwithstanding any other general or special law or procedural rule to the contrary, service on the defendant shall not be required until the period provided in paragraph (5). The attorney general may, for good cause shown, ask the court for extensions during which the complaint shall remain under seal. Any such motions may be supported by affidavits or other submissions under seal. The attorney general may elect to intervene and proceed with the action on behalf of the commonwealth or political subdivision within the 120–day period or during any extension, after the attorney general receives both the complaint and the material evidence and information. Any information or documents furnished by the relator to the attorney general in connection with an action or investigation under said sections 5B to 5O, inclusive, shall be exempt from disclosure under section 10 of chapter 66.

(4) Before the expiration of the initial 120 day period or any extensions obtained under paragraph (3), the attorney general shall; (i) assume control of the action, in which case the action shall be conducted by the attorney general; or (ii) notify the court that he declines to take over the action, in which case the relator shall have the right to conduct the action.

(5) If the attorney general decides to proceed with the action, the complaint shall be unsealed and served promptly thereafter. The defendant shall not be required to respond to any complaint filed under said sections 5B to 5O, inclusive, until 20 days after the complaint is unsealed and served upon the defendant pursuant to rule 4 of the Massachusetts rules of civil procedure.

(6) When a relator brings an action pursuant to this section, no person other than the attorney general may intervene or bring a related action based on the facts underlying the pending action.

(7) With respect to any federal, state or local government that is named as a co-plaintiff with the commonwealth in an action brought pursuant to sections 5B to 5O, inclusive, a seal on the action ordered by the court under paragraph (3) shall not preclude the commonwealth or the relator from serving the complaint, any other pleadings or the written disclosure of substantially all material evidence and information possessed by the relator on the law enforcement authorities that are authorized under the law of that federal, state or local government to investigate and prosecute such actions on behalf of such governments, except that such seal shall apply to the law enforcement authorities so served to the same extent as the seal applies to other parties in the action.