((a)) ** .—** A contractor receiving an operating-differential subsidy, or a charterer under chapter 575 of this title, may not continue as a party to or conform to an agreement with another carrier by water, or engage in a practice in concert with another carrier by water, that is unjustly discriminatory or unfair to any other citizen of the United States operating a common carrier by water employing only vessels documented under the laws of the United States on an established trade route from and to a United States port.

((b)) ** .—** No payment or subsidy of any kind may be paid, directly or indirectly, out of funds of the United States Government to a contractor or charterer that has violated subsection (a).

((c)) ** .—** A person whose business or property is injured by a violation of subsection (a) may bring a civil action in the district court of the United States for the district in which the defendant resides, is found, or has an agent. If the person prevails, the person shall be awarded—

((1)) 3 times the damages; and

((2)) costs, including reasonable attorney fees.