Microsoft's shared source licenses

Zac Bowling zac at
Sat Apr 29 08:19:01 UTC 2006

So what do you guys think of the new Microsoft shared source licences?

The FSF of Europe said that 2 licenses (MS-PL and MS-CL) are both
free/open source compatible licenses.

Its funny that they list those 5 because most of the big code is
released under another license similar to the one below I talk about.

I'm one of the developers on the Mono project. We are scared of
Microsoft shared source licenses in general. We started reimplementing
the .NET framework in Mono against the publicly filed standards
Microsoft released to ECMA years before Microsoft's released the shared
source version of .NET Framwork (codename Rotor).

When it came out, we were absolutely scared after looking at the license
to even open the code, even though one of the listed things you can do
with it on the page says: "People developing their own CLI
implementations will find the Shared Source CLI an indispensable guide
and adjunct to the ECMA standards."

The lawyers at Novell warned us about it too. In fact even though it
says that, we do not allow contributions from people that admitting have
even downloaded or looked at that code for fear of that nasty license.  

That license is nothing like the one they list on their homepage. Then
look at IronPython's license:

Very similar. I see this one most in a lot of Microsoft applications. A
few terms in there scare me. 

What do you guys think?

Currently we release our class libraries are released under a
MIT/X11/ZLib/BSD(modified) like license (whatever you want to call it
today). Our runtime is LGPL, and our C# compiler is GPLv2. 


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