Total, the French oil group, has threatened to launch legal action against InterContinentalExchange, the online commodities exchange, over its plan to pay out $67.5m to its B shareholders.
The move by Total, one of the original backers of ICE when the exchange was set up in May 2000, adds uncertainty to the payment to the B shareholders.
ICE first mooted the payment in June in an effort to appease discontented shareholders. They have yet to receive any money for selling their interests three years ago in the London-based International Petroleum Exchange, the world's second-largest energy futures exchange.
The original payment was conditional on the IPE moving to electronic trading.
IPE members, many of whom are B shareholders, received a letter this week highlighting the latest twist to this long-running saga.
The letter said that the payment had been held up because of the threat of legal action by one of the A shareholders on ICE and its directors, and that any decision had to wait until the issue was resolved.
Although Total was not mentioned by name in the letter, sources close to the IPE said that the French company was behind the threat after voting against the proposal this month.
Total, which owns about 4 per cent of ICE, would make no comment. A spokeswoman for ICE said that the exchange would not comment on any potential litigation issues, and was working hard to settle the dispute.
Total's stance is in contrast to the overwhelming majority of shareholders - more than 90 per cent of both A and B classes - of the Atlanta-based commodities exchange who approved the payment. ICE's other shareholders include Goldman Sachs, Morgan Stanley, Deutsche Bank and BP.
Total has taken the view that ICE was under no obligation to make the payment to B shareholders because the original criterion for making the pay-out was not met. As part of the takeover, ICE promised to pay the B shareholders 12 months after the IPE had gone fully electronic.
The lack of any cash payment since the takeover from ICE had created friction between IPE members and its owners, which led to ICE's decision to waive one of its original takeover conditions in order to allow early payment to B shareholders.
Following this decision, IPE's management decided to shorten the opening hours of pit trading from November 1 in an effort to stimulate more screen trading, which only accounts for 4 per cent of total IPE turnover in Brent crude oil contracts.