The fact that Microsoft has been in a frenzy of patenting its web services work shouldn't surprise anyone. So has IBM, and to such an extent that Redmond is justified in regarding its own vast list of claims as defensive.
But an umbrella claim that protects its .NET APIs, granted last week, highlights the extent of its determination to protect its interfaces. This claim references eight others filed in July 2001. As you can see from this diagram, it's fairly comprehensive.
A patent could lead to royalty claims against unauthorized attempts to clone portions of .NET, such as the Mono Project and DotGNU Portable.NET .
Mono developers had been confident that "its basic functional capabilities have pre-existed too long to be held up by patents. The basic components of Mono are technologically equivalent to Sun's Java technology, which has been around for years," according to the Mono FAQ.
Which remains as true today as it did two weeks ago, before the .Everything patent was granted.
Mono's plan was as follows:
"If Microsoft does patent some technology, then our plan is to either (1) work around it, (2) chop out patented pieces, (3) find prior art that would render the patent useless. "
Well, (1) is a declaration of intent, not a strategy; (2) would render the project useless, surely rendering the project as nothing but witty comments around some substantial chunks of #ifdef'd-out source code, which leaves us with three.
Now before going into Chicken-Licken mode - remember that a patent grant doesn't necessarily mean it's going to be enforced and that if even a tiny fraction of one percent of computer patents were enforced we'd have to unplug every machine in the world - let's have a look at the last paragraph of this patent:
 Although the invention has been described in language specific to structural ii features and/or methodological acts, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific features or acts described. Rather, the specific features and acts are disclosed as exemplary forms of implementing the claimed invention.
Which is a little strange and ominous after Microsoft sent the US Patent Office 30MB of API help files. Is this a specific protection of .NET APIs or a general claim to have invented web services, or indeed networked client-server computing, the universe, and everything? The details suggest the former, but section 101 suggests the latter.
If Java provides .NET with prior art, perhaps Sun could help out the Mono Project here, although there's little incentive for it do so, and every reason for it to respond with a "we told you so."
Historically Microsoft has not used patents to protect its business, preferring to tinker with the APIs themselves. Quite explicitly, as Brad Silverberg told Andrew Schulman in 1993: if Microsoft stops "evolving" the APIs they become commoditized. This policy, we can assume, is changing.
And to think only a year ago there was talk of basing GNOME on .NET APIs.
" How much do you love Microsoft's .NET? Enough to trust your Gnome applications to its APIs in the future?" we asked then.
Gnome to be based on .NET - de Icaza
Anders Heljsberg on what's next for C#
BETRAYAL! .NET clones and GNOME in the firing line
Call my bluff - how smart is reverse engineering .NET?
Why it pays to embrace and extend .NET - de Icaza
Borland thinks Mono for open source .NET challenge [Borland now a .NET licensee]