With the US government quietly agreeing to cease its antitrust oversight of Microsoft earlier this month, you might have assumed that the software giant's legal wrangling over its one-time market power was a thing of the past. Well, not yet it isn't: This week, Microsoft revealed that it will appeal an "excessive" $1.35 billion fine that was imposed on it by overzealous European Union (EU) antitrust regulators in 2008.

"The fine related to the price Microsoft had proposed for one of several forms of licenses for the technology Microsoft was required to make available by the Commission's 2004 decision," a Microsoft statement reads. "This appeal is limited to this one narrow issue. Microsoft has been working in full cooperation with the [European] Commission."

"This case would not have arisen if the Commission had been as explicit with respect to rates which it wanted Microsoft to charge as it had been with all other terms of licensing proposed by Microsoft," Jean Francois Bellis, a Microsoft lawyer, said this week at a hearing before the European General Court. The fine was "most undeserved," he added.

Microsoft's hopes of recouping the fine are slim, however. Legal experts in Europe say that the EC gets wide discretion in its fining abilities, and the EU's courts have rarely overruled such fines. (However, the amount of Microsoft's fine was historic, it should be noted.)

"Microsoft is acting like a gambler who doubled up on a losing bet, and now wants his money back," EC representative Nicholas Kahn said at the hearings.

Microsoft settled with EU antitrust regulators in late 2009. Until that point, the software giant had been fairly belligerent in its dealings with the EC and was fined several times for failing to meet schedules and requirements. This issue represents the biggest part of that fine structure.

If you're sitting on the edge of your seat waiting to see how this issue is resolved, don't bother: We won't learn the outcome of this appeal for at least 6 months. In fact, the court has up to a year to rule.