49 U.S.C. § 14904

(a) Rebates by Agents .— A person, or an officer, employee, or agent of that person, that— (1) offers, grants, gives, solicits, accepts, or receives a rebate for concession, in violation of a provision of this part related to motor carrier transportation subject to jurisdiction under subchapter I of chapter 135; or (2) by any means assists or permits another person to get transportation that is subject to jurisdiction under that subchapter at less than the rate in effect for that transportation under section 13702, is liable to the United States for a civil penalty of $200 for the first violation and $250 for a subsequent violation. (b) Undercharging.— (1) Freight forwarder .— A freight forwarder providing service subject to jurisdiction under subchapter III of chapter 135, or an officer, agent, or employee of that freight forwarder, that assists a person in getting, or willingly permits a person to get, service provided under that subchapter at less than the rate in effect for that service under section 13702, is liable to the United States for a civil penalty of not more than $500 for the first violation and not more than $2,000 for a subsequent violation. (2) Others .— A person that by any means gets, or attempts to get, service provided under subchapter III of chapter 135 at less than the rate in effect for that service under section 13702, is liable to the United States for a civil penalty of not more than $500 for the first violation and not more than $2,000 for a subsequent violation.