15 U.S. Code § 3414 - Enforcement
It shall be unlawful for any person to violate any provision of this chapter or any rule or order under this chapter.
Except as provided in paragraph (2), whenever it appears to the Commission that any person is engaged or about to engage in any act or practice which constitutes or will constitute a violation of any provision of this chapter, or of any rule or order thereunder, the Commission may bring an action in the District Court of the United States for the District of Columbia or any other appropriate district court of the United States to enjoin such act or practice and to enforce compliance with this chapter, or any rule or order thereunder.
Whenever it appears to the President that any person has engaged, is engaged, or is about to engage in acts or practices constituting a violation of any order under section 3362 of this title or any order or supplemental order issued under section 3363 of this title, the President may bring a civil action in any appropriate district court of the United States to enjoin such acts or practices.
In any action under paragraph (1) or (2), the court shall, upon a proper showing, issue a temporary restraining order or preliminary or permanent injunction without bond. In any such action, the court may also issue a mandatory injunction commanding any person to comply with any applicable provision of law, rule, or order, or ordering such other legal or equitable relief as the court determines appropriate, including refund or restitution.
The Commission may transmit such evidence as may be available concerning any acts or practices constituting any possible violations of the Federal antitrust laws to the Attorney General who may institute appropriate criminal proceedings.
For purposes of this paragraph, in the case of a continuing violation, each day of violation shall constitute a separate violation.
No person shall be subject to any civil penalty under this paragraph with respect to any violation occurring more than 3 years before the date on which such person is provided notice of the proposed penalty under subparagraph (E). The preceding sentence shall not apply in any case in which an untrue statement of material fact was made to the Commission or a State or Federal agency by, or acquiesced to by, the violator with respect to the acts or omissions constituting such violation, or if there was omitted a material fact necessary in order to make any statement made by, or acquiesced to by, the violator with respect to such acts or omissions not misleading in light of circumstances under such statement was made.
Before assessing any civil penalty under this paragraph, the Commission shall provide to such person notice of the proposed penalty. Following receipt of notice of the proposed penalty by such person, the Commission shall, by order, asssess  such penalty.
If the civil penalty has not been paid within 60 calendar days after the assessment order has been made under subparagraph (E), the Commission shall institute an action in the appropriate district court of the United States for an order affirming the assessment of the civil penalty. The court shall have authority to review de novo the law and the facts involved, and shall have jurisdiction to enter a judgment enforcing, modifying, and enforcing as so modified, or setting aside in whole or in part, such assessment.
Except in the case of violations covered under paragraph (3), any person who knowingly and willfully violates any rule or order under this chapter (other than an order of the Commission assessing a civil penalty under subsection (b)(4)(E)), shall be subject to a fine of not more than $50,000 for each day on which the offense occurs.
For purposes of this subsection, each day of violation shall constitute a separate violation.
 So in original. Probably should be “assess”.
2005—Subsec. (b)(6)(A). Pub. L. 109–58, § 314(b)(2), substituted “$1,000,000” for “$5,000” in cl. (i) and “$1,000,000” for “$25,000” in cl. (ii).
Subsec. (c)(1). Pub. L. 109–58, § 314(a)(2)(A), substituted “$1,000,000” for “$5,000” in subpar. (A) and “5 years” for “two years” in subpar. (B).
Subsec. (c)(2). Pub. L. 109–58, § 314(a)(2)(B), substituted “$50,000 for each day on which the offense occurs” for “$500 for each violation”.
1989—Subsec. (a). Pub. L. 101–60, § 3(b)(6), struck out par. (2) designation and par. (1) making it unlawful to sell natural gas at a first sale price in excess of any applicable maximum lawful price under this chapter.
Subsec. (b). Pub. L. 101–60, § 3(a)(4), substituted “paragraph (2)” for “paragraphs (2) and (3)” in par. (1), struck out par. (3) which related to enforcement of incremental pricing, and substituted “paragraph (1) or (2)” for “paragraph (1), (2), or (3)” in par. (4).