; and (ii) by striking reduce the amount of the liability or penalty provided for in this section and inserting reduce the amount of the penalty under paragraph (3) ; (E) by striking paragraph (5) and inserting the following: (5) A person (including a representative of employees or a unit of local government aggrieved under paragraph (1) or (3)) seeking to enforce the liability provided for in this section, may, either for such person, for other persons similarly situated, or for both, bring suit in any district court of the United States for any district in which the violation is alleged to have occurred or in which the employer transacts business. ; and (F) in paragraph (6), by striking prevailing party and inserting prevailing plaintiff ; (2) by redesignating subsection (b) as subsection (c); (3) by inserting after subsection (a) the following: (b) Limitations An action shall be brought under this section not later than 4 years after the date of the last event constituting the alleged violation for which the action is brought. ; (4) by adding at the end the following: (d) Exemption from liquidated damages Notwithstanding subsection (a)(1)(C), an employer is not liable for the liquidated damages described in such subsection if— (1) the employee alleges a site closing and— (A) the employer can establish that circumstances described in section 3(c)(1) existed on the 60th and 30th days before the site closing; or (B) the site closing is due to any form of natural disaster or directly due to a terrorist attack