BRUSSELS, Belgium - Microsoft Corp. said Wednesday it will license its Windows source code to comply with a European Union antitrust ruling.
The source code provides the building blocks of the operating system that competitors need to make products compatible with Windows.
The company's chief counsel Brad Smith said called the move "a bold stroke."
Microsoft has refused to license the source code in the past. Software developers still will have to pay for the code, which open source advocates will not be allowed to "publish for free," Smith cautioned. The company had "just started to provide this information on both sides on the Atlantic" and regulators "want to see all the details," Smith added.
In March 2004, the EU executive levied a record euro497 million ($613 million) fine against Microsoft, ordered it to share code with rivals and offer an unbundled version of Windows without the Media Player software for what the court saw as an abuse of the company's dominant position in the industry.
Last month, the European Commission threatened to fine Microsoft up to euro2 million ($2.36 million) a day backdated to Dec. 15 for failing to obey, saying the software giant was proving intransigent about sharing data with competitors.
Microsoft has launched a legal challenge that will be heard by the European Court of First Instance on April 24-28. The court - the second-highest in the European Union - stressed that the dates for the hearing were provisional and could still be changed.
Smith told a news conference he was "confident" of winning the case.
Earlier, the EU had repeated its complaints that Microsoft was not complying with its demands.
"Microsoft is not disclosing complete and accurate interface information to allow non-Microsoft workgroup servers to receive full interoperability with Windows PCs and servers," said EU spokesman Jonathan Todd.
He said EU regulators took note that the U.S. Department of Justice was also claiming that Microsoft was failing to provide the technical information asked for in a DOJ settlement.
In December, Microsoft said the EU Commission was trying to undermine its Windows operating system with ever-more-drastic demands for technological transparency, and that it would contest the measure under EU law.
Todd said this was untrue. "We are not moving the goalposts as has been suggested," he said. "We are not changing our demands."
"The Commission's position is that Microsoft is obliged to comply with the remedies imposed in the Commission's March 2004 decision - nothing more, nothing less."
Todd stressed that the final word on whether Microsoft is meeting the terms of the EU antitrust order "rests in the first place with the Commission and not Microsoft."
Microsoft claims the EU demands on opening up its software specifications would also open the door to the cloning of the company's core product, the ubiquitous Windows operating system.
The company has until Feb. 15 to formally answer the complaint. It planned to make a statement to reporters later Tuesday.