Commission of the European Communities v. Microsoft Corporation


On December 10, 1998, Sun Microsystems lodged a complaint with the European Commission relating to Microsoft Corporation’s refusal to give Sun the information and technology necessary to allow its work group server operating systems to interoperate effectively with the Windows client PC operating system. Thereafter, the Commission, acting on its own initiative, launched an investigation relating to (1) Microsoft’s Windows 2000 generation of client PC and work group server operating systems and (2) the integration by Microsoft of its Windows Media Player in its Windows client PC operating system.  The Commission subsequently found that Microsoft (1) had dominant positions in the markets for client PC operating systems and work group server operating systems and (2) had abused its dominant positions in violation of Article 82 EC and Article 54 of the Agreement on the European Economic Area (EEA). 

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Teaching Note:
Suggested Citation:

Constance E. Bagley, “ Commission of the European Communities v.  Microsoft Corporation,” Yale SOM Case 07-054, November 21, 2007

  • Microsoft
  • European Union
  • Law & Contracts
  • State & Society