Microsoft has not said this to my knowledge and I follow the issue closely.
They have said that Novell users are free to use it due to their agreement
not to sue each other and it protects Novell users only. If you have info to
the contrary please post it as I would like to see it.

http://www.osnews.com/story/8712
searchwindevelopment.techtarget.com/news/article/0,289142,sid8_gci1019210\
,00.html

This is a direct answer by Microsoft about Mono:

"No, Microsoft does not support the Mono product, nor has it licensed
anything to Novell/Ximian. Mono is an attempt by Novell to reverse engineer
parts of Microsoft's .NET Framework. It is not an extension of the .NET
Framework and it should not be considered as such."

Recently Miguel de Icaza said that he faulted Microsoft for not getting
behind Mono. This has stunted Mono's growth in his opinion and he calls it a
lost opportunity for Microsoft and .NET. This was published in the San Diego
Times and later pulled.
www.the-source.com/.../

This is a quote from Wikipedia: "Microsoft holds software
patents<en.wikipedia.org/wiki/Software_patents>over some of the
technologies in Mono."