Here's a look at how a 1998 complaint by Sun Microsystems led to Microsoft receiving fines totaling (EURO)2.2 billion - $2.9 billion at today's exchange rates.
The Sun complaint was that Microsoft wouldn't turn over technical documents needed to build interfaces between their products. Over the years, the EU broadened its investigation to include whether Microsoft had abused Window's near-monopoly over the market for computer operating systems to corner other markets, including server software, streaming media software, and Internet browsers.
Here's how the case developed
March 24, 2004
The European Commission finds Microsoft guilty of breaking competition law and abusing its dominance in the operating system market. It fines the company (EURO)497 million. It also orders Microsoft to share technical documents with rivals and market a version of Windows without a media player.
June 15, 2005
After losing an appeal, Microsoft makes Windows XP N - without Media Player - available. There are few takers. The same month, EU also raises concerns about the usability of Microsoft's technical documents.
July 12, 2006
EU decides Microsoft isn't obeying the 2004 decision and penalizes it an additional (EURO)280.5 million.
March 1, 2007
EU threatens Microsoft with even more penalties, accusing the company of further noncompliance by setting royalty fees too high for technical documents.
October 22
Microsoft agrees to slash fees for the technical documents. It also offers access to open source developers and others for a one-time fee of (EURO)10,000. Though this resolves key parts of the dispute, but the EU says Microsoft is still subject to penalties for its noncompliance until then.
January 14, 2008
Following a complaint by Web browser developer Opera Software ASA, the EU announces it is investigating Microsoft again. This time, it's on suspicion of squeezing rival Internet browsers and software rivals dependent on Microsoft programs out of the market.
February 27
EU regulators impose a (EURO)899 million penalty - a record at the time - for failing to fully comply with the 2004 antitrust order. This is on top of the fine imposed in 2004 and the penalty of 2006 and brings the total to nearly (EURO)1.7 billion.
May 9
Microsoft announces it has appealed the penalty.
January 16, 2009
The European Commission orders Microsoft to untie its Internet Explorer browser from Windows.
July 24
Microsoft agrees to offer a choice of rival Web browsers on Windows to ward off new European Union antitrust fines.
December 16
The European Union drops the browser case after Microsoft's offer to give Windows users in Europe a choice of up to 12 other Web browsers. This ends all of the EU's active cases against Microsoft, though the appeal of the 2008 fine remains pending.
June 27, 2012
The General Court of the European Union rejects Microsoft's appeal of the 2008 penalty, but reduces it to (EURO)860 million.
March 6, 2013
The EU fines Microsoft (EURO)561 million for failing to offer users a choice of browsers when they installed a version of Windows 7. The failure went on for 16 months and affected 15 million operating system installations. Microsoft acknowledged the failure and apologized.
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