Except as otherwise provided in subsection (b), any person may commence a civil action against—

(1) any manufacturer or private labeler who is alleged to be in violation of any provision of this part or any rule under this part;

(2) any Federal agency which has a responsibility under this part where there is an alleged failure of such agency to perform any act or duty under this part which is not discretionary; or

(3) the Secretary in any case in which there is an alleged failure of the Secretary to comply with a nondiscretionary duty to issue a proposed or final rule according to the schedules set forth in section 6295 of this title.

No action may be commenced—

under subsection (a)(1)—

(A) prior to 60 days after the date on which the plaintiff has given notice of the violation (i) to the Secretary, (ii) to the Commission, and (iii) to any alleged violator of such provision or rule, or

(B) if the Commission has commenced and is diligently prosecuting a civil action to require compliance with such provision or rule, but, in any such action, any person may intervene as a matter of right.

(2) under subsection (a)(2) prior to 60 days after the date on which the plaintiff has given notice of such action to the Secretary and Commission.

In such action under this section, the Secretary or the Commission (or both), if not a party, may intervene as a matter of right.

The court, in issuing any final order in any action brought pursuant to subsection (a) of this section, may award costs of litigation (including reasonable attorney and expert witness fees) to any party, whenever the court determines such award is appropriate.

Nothing in this section shall restrict any right which any person (or class of persons) may have under any statute or common law to seek enforcement of this part or any rule thereunder, or to seek any other relief (including relief against the Secretary or the Commission).

For purposes of this section, if a manufacturer or private labeler complied in good faith with a rule under this part, then he shall not be deemed to have violated any provision of this part by reason of the alleged invalidity of such rule.

(Pub. L. 94–163, title III, § 335, Dec. 22, 1975, 89 Stat. 930; Pub. L. 95–619, title IV, § 425(f), title VI, § 691(b)(2), Nov. 9, 1978, 92 Stat. 3266, 3288; Pub. L. 100–12, §§ 8, 11(b)(7), Mar. 17, 1987, 101 Stat. 122, 126.)