The news has been welcomed by the companies, which have already paid out millions for conspiring to fix prices on human and animal vitamins.
Roche and BASF pleaded guilty to taking part in a worldwide conspiracy in 1999, agreeing to pay a total of $725 million in fines. Merck, Degussa, Lonza, Takeda Chemical Industries, Daiichi Pharmaceutical and Eisai also pleaded guilty to the charges.
Since then, a further $2 billion has been paid by vitamin makers through civil lawsuits in US courts.
But non-US customers, including an Ecuadorian fishery and an Australian pig farm, are also seeking to take advantage of the US antitrust case.
According to a Bloomberg report, Justice Stephen G. Breyer said that the previous ruling allowing non-US customers to bring the case "creates a serious risk of interference with a foreign nation's ability independently to regulate its own commercial affairs".
However the foreign customers may still be able to argue that vitamin prices in the US are intricately tied to those abroad because of bulk vitamins' status as commodities.
BASF however said in a statement that it was "confident that the company will continue to prevail" in the case.