It is a case that has been rumbling for over 4 years and now it's set to continue.
Microsoft has appealed a landmark fine by the EU, which was the largest ever imposed by the European Commission, and would see it having to raid its coffers for 899m euros or around £680.9m.
The fine was dolled out after the EU found the computing giant guilty of defying sanctions imposed on it for anti-competitive behaviour way back in 2004.
Microsoft was accused of not providing key information to rival software makers that would allow them to develop software for Microsoft platforms.
Microsoft says that it wants to seek "clarity from the court", while European authorities are standing firm that the fine is deserved.
In the meantime, two separate anti-trust, or competitions, investigations are taken place.
The EC launched the cases last month and is to probe whether Microsoft is still unfairly dominating the PC software market and also whether it is amking its products incompatible with rival software on purpose.