Microsoft filed a brief with the US Supreme Court yesterday, taking an incremental step in its efforts to get its antitrust case against the US government reviewed by the nation's highest court.

The submission, a standard step in the review process, asks the Supreme Court to immediately review a ruling by the US Court of Appeals for the District of Columbia that upheld a lower court ruling. This ruling said that Microsoft used its monopoly power in the desktop operating system market to squash competition in other markets.

Wednesday's submission contains eight arguments that counter the points outlined in the Justice Department's brief, issued on 31 August, calling for the Supreme Court not to hear the case.

Microsoft first asked for its case to be reviewed by the Supreme Court on 7 August, arguing that District Court Judge Thomas Penfield Jackson (the original trial court judge who ruled against Microsoft last year) should have been disqualified from the case before he ever made his ruling. Jackson was admonished by the Appeals Court for speaking to the press during the trial. That court overturned his ruling for a remedy.

A disqualification would have the effect of vacating the District Court's findings of fact and conclusions of law, Microsoft said.