Companies ranging from Hyundai and Kia to Campbells Soup are suing the railways, which are accused of imposing the surcharges between July 2003 and December 2008.

Many of the filings, including that submitted by Hyundai and Kia to the federal court in Santa Ana, California, cite meetings, phone calls and emails to allege that the railways conspired to impose fuel surcharges, under the guise of a fuel cost recovery programme, that ultimately generated billions of dollars in profit at customers’ expense.

According to an independent study, the lawsuits state that the railways’ fuel surcharge revenue exceeded their fuel costs by more than $US 6bn between 2003 and March 2007.

Price-fixing allegations have been making their way through the US court system for years, with several companies filing similar lawsuits in 2007. These cases sought class-action on behalf of 16,000 shippers against the four Class 1s. However, in August, a federal appeals court in Washington, DC, ruled that nationwide litigation over the surcharges could not proceed as a class action because more than 2000 members of the proposed class were not harmed.

Instead the judge said that cases would have to be brought individually or broken down to include smaller groups of shippers with similar situations. The deadline for filing these complaints was October 1.

In previous stages of the lawsuits, the railways have generally argued that fuel surcharges are common across the transport sector, that they were legal and were intended to recover costs from the increasing price of fuel at the time.