For Approval: Microsoft Permissive License

Donovan Hawkins hawkins at
Sat Aug 11 00:33:50 UTC 2007

On Fri, 10 Aug 2007, Chuck Swiger wrote:

> On Aug 10, 2007, at 4:35 PM, Donovan Hawkins wrote:
>> The MozPL also has an explicit statement in section 13 that permits the 
>> initial release under MozPL combined with another license. Both the MicroPL 
>> and MicroCL lack a clause like that. While I doubt the license agreement 
>> could prevent the original author from releasing under as many licenses as 
>> he chooses, it seems like a similar clause would clear up misunderstandings 
>> in cases where both releases come packaged together with a single license 
>> document (a very likely scenario).
> Clause 2(a) and 3(d) suggest that you can prepare and distribute derivative 
> works, so long as the source code which was originally licensed under the 
> MSPL remains under the MSPL.  There are no explicit restrictions against 
> combining such code with source code under other licenses, unless the other 
> license forbids the combination.  In other words, the MSPL + 
> BSD/MIT/Zlib/Apache2 code is fine, but MSPL+GPL or similar is not.

I wasn't referring to derivative works, I was referring to the original 
work. If I create an original program and want to license under both the 
MSPL and the GPL, the MSPL implies that I can't do it. I'm sure that's not 
actually the case, but I think it would be less confusing if that were 
made explicit. I imagine that's why MPL has clause 13.

>> Also, isn't the name "Permissive" rather misleading?  While you are free to 
>> release binaries however you choose, the license is viral and the source 
>> code cannot be used by the vast majority (ie, any) of the existing 
>> open-source projects. I would hardly call that permissive...the word 
>> carries a lot more meaning than "non-copyleft".
> A "viral" license is one which requires that a combination of code under that 
> license and other software, to only be distributed under the terms of the 
> viral license.  The MSPL isn't viral in that sense; instead, it is reasonably 
> close to the "new" or "modified" BSDL, which is considered a canonical 
> example of a permissive license.

Well, it replicates in the sense that all derivative works are partially 
released under it, but I see your point. My point was that it permanently 
taints the source code in a way that makes it incompatible with nearly 
every popular open-source license, requiring that developers put big 
orange tape around the MSPL-licensed code to indicate it is forever under 
the MSPL.

I can think of cases where I made MAJOR changes to some open-source 
function to use in a project...what sort of Frankenlicense would apply to 
that function if I wished to release my changes under GPL but the original 
was MPL or MSPL? Every other line of code under a different license? That 
same point was apparently also missed in the MSCL if it tries to copyleft 
a "file" that contains MSCL code.

It's fine if the MSPL want to place a restriction like that...obviously 
the MPL is the same way...but it's not what I would call permissive. 
Modified BSD is basically public domain with a disclaimer, and because of 
that it is compatible with just about everything. Neither the MPL nor the 
MSPL offer the same level of fact, the MSPL isn't even 
compatible with the MSCL. I'm surprised if people consider the MPL a 
"permissive" license...I'd consider that an unfortunate overgeneralization 
of the idea that all licenses are either permissive or copyleft.

My only point was that having "Permissive" in the title is confusing, much 
as having "Open" in the title would be confusing if it wasn't, in fact, 

Donovan Hawkins, PhD                 "The study of physics will always be
Software Engineer                     safer than biology, for while the
hawkins at                   hazards of physics drop off as 1/r^2,                biological ones grow exponentially."

More information about the License-discuss mailing list