Allow me to point out some problems in your postulations:

1. Microsoft’s patent promise does not cover “all of us” even for the ECMA standard parts. The promise only covers implementations “the extent it conforms to one of the Covered Specifications, and is compliant with all of the required parts of the mandatory provisions of that specification”.[1]

So that means you are not covered if you are implementing partial, specialized or modified versions. A pedantic reading would be that you can’t even get started on an implementation, because it is unlikely your first releases will be “compliant with all of the required parts of the mandatory provisions”.

This suits Novell just fine, because they have an additional agreement with Microsoft and do not have to rely on the Community Promise.

So, even the ECMA bits have concerns.

2. Linux programs, including “marquee” applications like Banshee use non-ECMA portions. There are many more sections besides Winforms and ADO.NET that are not covered.

In fact, there are at least 17 namespaces that are not standardized, including System.Linq – a feature supporters love to praise about .NET/C#. [2]

So, even “Linux programs” do have quite an interest in “using those parts”.

3. There is no question that Microsoft has “patents on .NET” – the crudest and quickest search possible shows that. [3]

What no one can be clear on how a judge and jury will decide that a program infringes, which is exactly what Microsoft banks on. Because no one wants to go to court to find out – it is the risk that is the weapon. The threat of court is the weapon.

Furthermore, the idea that so-called “alternatives” to Mono present the same level of risk is absurd. By definition, Microsoft technologies come from Microsoft, and therefore have a much higher chance of being specifically patented by Microsoft.

By extension, “alternatives” that potentially infringe are much more likely to do so in a manner that can be defended by prior use or obvious extensions by a practitoner of the art. So even if they do offend it would be because they are attempting to solve a similar problem, not because they are blatantly copying a patented technology.

The issue is not “alleged patents”. Microsoft holds over 10 thousand patents – many of which specifically mention “C#”, “.NET framework”, “managed runtime” and so on. A “few hundred dollars for a professional patent search” is not really going to provide a definitive answer.

The issue – rather, one of the issues – is that some people consider the level of risk unacceptable. That is a rational position, and quite hard to argue with – because no one can honestly say there is no level of risk – and “poo-pooing” people’s concerns with weak arguments does not allay concerns. Quite the contrary.

[1] http://www.microsoft.com/interop/cp/default.mspx
[2] http://en.wikipedia.org/wiki/Base_Class_Library#Non_standardized_namespaces
[3] http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=%2Fnetahtml%2FPTO%2Fsearch-adv.htm&r=0&f=S&l=50&d=PTXT&RS=%28AN%2FMicrosoft+AND+ACLM%2FNET%29&Refine=Refine+Search&Refine=Refine+Search&Query=AN%2FMicrosoft+AND+ACLM%2F%22NET+framework%22

1. Are not on the ECMA standard part of Mono (which is covered by Microsoft’s patent promise for all of us)

2. Would be infringed by programs that do NOT use Winforms, ADO.NET, and such? I am only interested in using Mono to write Linux programs, so have no interest in using those parts.

3. Are not also infringed by the alternatives to Mono on Linux, such as python, ruby, perl, and such?

There has been plenty of time to find these alleged patents. Some of the anit-Mono people (such as the FSF and the SFLC) surely can afford a few hundred dollars for a professional patent search, if the public search interface at the PTO is not sufficient.