Subparagraph (A) shall not apply with respect to the filing of an action by an attorney general of a State under this subsection, if the attorney general determines that it is not feasible to provide the notice described in that subparagraph before the filing of the action.
In an action described in clause (i), the attorney general of a State shall provide notice and a copy of the complaint to the Commission at the same time as the attorney general files the action.
On receiving notice under subsection (a)(2), the Commission shall have the right to intervene in the action that is the subject of the notice.
In any case in which an action is instituted by or on behalf of the Commission for violation of any regulation prescribed under section 6502 of this title, no State may, during the pendency of that action, institute an action under subsection (a) against any defendant named in the complaint in that action for violation of that regulation.
Any action brought under subsection (a) may be brought in the district court of the United States that meets applicable requirements relating to venue under section 1391 of title 28.