There was no question that Microsoft‘s buyout of Skype for $8.5 million USD was a big thing, both for users of the service and for both companies. Microsoft is working on bringing the two together in even more ways across Windows 8, Windows Phone, and more recently its newly-unveiled Xbox One console.

However, it’s not all rainbows and pearls for the software maker, as Cisco Systems Inc, the world’s leading network equipment maker — along with Italian fixed-line and Internet telephone provider Messagenet SpA — will try to convince Europe’s second highest court on Wednesday that it should overturn the EU’s approval of Microsoft’s purchase of Skype, a deal that was approved without Microsoft having to make any concessions, and one that Cisco feels was made with several “manifest errors” and is allowing Microsoft to be anti-competitive.

Cisco is expected to argue that the “combined company’s dominant share in the communications market gave it the ability and the incentive to refuse to provide data that would allow rivals to work with the merged firm’s products,” according to a Reuters report.

If Cisco is successful, it would be the first time a company has successfully battled against a merger approval since 2002’s case involving Sony Music and BMG. In most cases, the courts will side with the Commission’s decision. Do you think Cisco has a chance?