Except, said patent grant does not extend to people who don't work for de Icaza, people who distribute Mono, or people who use Mono, or people who have compiled C# apps with Mono.
Microsoft refuses to make Mono patent free, and anyone who distributes, uses, or distributes binaries compiled with Mono _can and will be sued_.
Not only is de Icaza not a competitor to Microsoft, he is helping Microsoft attack Linux and the Free Software movement.
Mono refuses to switch to a license, such as GPLv3, to protect users, distributors, and developers from the patents; not only do they refuse, they are getting rid of all GPLv2 code in favor of BSD code. Once Mono is BSDafied, Microsoft can import all code from Mono and close source it within the main C#/.Net implementation on Windows.