The Microsoft chief executive asserted that open source "is not free", and referred to the possibility that Microsoft may sue GNU/Linux vendors.

Today, there are reports that a US federal jury has found Microsoft infringed audio patents held by Alcatel-Lucent and should pay $US1.52 billion in damages! The boot, it would appear, is firmly on the other foot.

That is something for Ballmer to muse about in a quiet moment (if he ever has one).

These statements about IP violations in Linux are being made by the CEO of a company which is being sued by AT&T for sending development work overseas to avoid US patents. Lest we forget, this is the same company which was successfully sued by Eolas for infringing patents relating to browser plug-ins.

There's more. A small company named Visto is suing Microsoft for alleged mobile email and data patent infringements; another firm VirnetX is taking action against the Redmond giant for alleged patent infringement in VPN. Remember, Timeline successfully sued Microsoft for patent infringement in SQL Server.