Norway's Hoegh Autoliners is to pay a fine to end a car carrier price-fixing probe by the US Department of Justice (DOJ).
The $21m penalty relates to US to Middle East exports.
It said the investigation into the sector began in September 2012, with Hoegh one of several owners to be examined.
"Hoegh Autoliners has cooperated fully with the authorities," it said. "The investigation, covering the period 2001-2012, has been concluded, and Hoegh Autoliners has agreed a settlement with the DOJ."
The owner also pointed out that antitrust authorities in China, Japan, Mexico, New Zealand and South Korea have concluded their investigations and have not imposed fines on Hoegh.
Other jurisdictions are continuing probes.
“Hoegh Autoliners takes the Department of Justice’s conclusion very seriously, and we deeply regret the incidents occurred,”, said chairman Leif Hoegh.
“We would like to extend our sincere apologies to customers, personnel and other stakeholders. Hoegh Autoliners is committed to fair and lawful business practice."
He added: "Actions have been taken to strengthen our efforts to meet the highest ethical standards, and we will continue to reinforce our compliance activities throughout our organisation.”
Earlier this month, the company denied South African accusations over price-fixing in the car carrier trade.
The country's competition authority has claimed Hoegh colluded to fix rates with Japan's MOL.
It added that the shipowner had been referred for prosecution on seven charges relating to collusive tendering, price fixing and market division.
"From around 2009, MOL and Hoegh engaged in prohibited practices in that they agreed and/or engaged in concerted practices as competitors to fix prices, divide markets and tender collusively," it added.
Hoegh told Reuters: "We are not admitting any guilt and we will defend ourselves."
It added a probe had been continuing since 2013, but that the statement from the authority came as a surprise.
The authority recommended in March that MOL's compatriot K Line was fined 10% of its local turnover in a price-fixing case.
It found the owner was colluding with MOL, NYK and Wallenius Wilhelmsen Logistics (WWL) in the Toyota trade.
Earlier this year, Brazil’s competition authority launched formal proceedings to investigate nine car carrier operators, including Hoegh.
The company was also facing a class action in the US from car buyers.