Symantec's chief executive officer yesterday downplayed reports that his company had taken the first steps in a possible European Commission anti-trust investigation into Microsoft's business practices.

John Thompson said that the relationship between the two companies was one of "mutual dependency". "We have hundreds of millions of users in the Windows operating environment," Thompson told a Commonwealth Club audience "We make the Windows experience secure, and therefore there's a mutual dependency between us and Microsoft."

Last Thursday, Dow Jones reported that Symantec had made an "informal" complaint against Microsoft to the EC, a possible precursor to anti-trust action. Last year the EC ordered Microsoft to pay €497 million in fines and to ship a version of Windows that did not include the Windows Media Player, ending a five-year anti-trust investigation into the company.

Thompson confirmed that his company had provided documents to the European Commission, but he dismissed the report, which had cited unnamed sources. "We're not involved in any investigation," he said. "We partner with Microsoft," he said. "We're not trying to go to court with Microsoft by any stretch of the imagination."