Already facing two probes by the European Union, Microsoft is now confronted with a third over lobbying for its OOXML file format for its Office productivity software.
European regulators have begun an investigation into Microsoft's activities as it worked to gain approval for its OOXML formats, which are implemented in Microsoft Office 2007. The investigation was reported in Friday's Wall Street Journal.
Microsoft is hoping to position OOXML as an alternative to the Open Document Format, which has already received International Standards Organization (ISO) approval.
Microsoft has lined up a group of vendors supporting its effort, while another group, led by IBM, has opposed Microsoft in a long-running battle over office software formats. The anti-Microsoft group maintains that Microsoft's OOXML formats are so complex that only Microsoft can fathom them. Microsoft maintains that the new OOXML formats are open.
"The investigation will be especially welcome in standards circles, due to the wide range of reports from the field that Microsoft has engaged in 'stacking' of the national committees that were voting on OOXML as well as other overreaching activities intended to influence the result" of standards voting, said Andrew Updegrove, a standards expert who has opposed the Microsoft effort in the past, in an e-mail.
In the past, Microsoft has complained that the companies opposing its OOXML have engaged in intense lobbying over formats. The software maker declined to comment on the Wall Street Journal report.
Microsoft's OOXML proposal is still working its way through international standards bodies but has had a tough time convincing standards groups.
In September, a proposal that called for OOXML to receive fast-track approval was voted down by the ISO in Geneva by standards groups from participating countries.
Microsoft is already facing EU investigations involving the integration of its Internet Explorer browser into Office software and involving how its Office software operates with competitors' software.