A spokesman for the Commission said that the withdrawal of Novell, a business software company, and the Computer and Communications Industry Association (CCIA), whose members include Yahoo! and Oracle, had not damaged its argument that Microsoft abused its dominance of the software market.

Bo Vesterdorf, the president of the European Court of First Instance in Luxembourg, called today’s meeting after two days of hearings last month to consider suspending EU sanctions that would force Microsoft to sell a version of Windows without its Media Player audio-visual software.

Mr Vesterdorf called the new meeting to consider the impact of the moves by Novell and CCIA, a source familiar with the situation said.

The meeting will include not only the current parties to the case but also those that have dropped out.

“The fact that certain parties have withdrawn doesn’t change the facts of the case at all,” said the spokesman for the commission.

The sole remaining company opposing Microsoft before the EU is RealNetworks, whose audio-visual software Real Player competes with Microsoft’s Windows Media Player.

The CCIA was one of the most outspoken opponents of Microsoft in its antitrust battle witht the Commission. In February it provided hundreds of pages of evidence outlining what it described as “the myriad anti-competitive abuses of Microsoft that remain at the heart of their ongoing business strategy”.

The CCIA and Novell removed themselves from the lawsuit after Microsoft agreed to pay each of them substantial sums in settlements. Microsoft is understood to have paid about $20 million (£10.6 million) to the CCIA, of which almost half went to Ed Black, president of the trade body.

Mr Black told The Times: “Neither the CCIA or me personally have rescinded our position on the case.

“We made a limited, tactical withdrawal from specific litigation, but all the evidence we have provided to the Commission stands, and will continue to stand.”

A spokesman for Microsoft said that the company would not seek to have any prior testimony or evidence in the case withdrawn from the judge’s consideration.

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