[Mono-list] MPL license

Jonathan Pryor jonpryor@vt.edu
Tue, 11 Jan 2005 06:50:57 -0500


On Tue, 2005-01-11 at 05:44 +0000, Fernando Silva wrote:
> (I'm sorry if this is not the best place to ask this question)

It certainly isn't the best place, though I'm not sure where would be
the best place.  I suspect that the debian-legal list could answer this
better:

	http://lists.debian.org/debian-legal/


> I want to develop some assemblies and license them under a MPL
> license. Basicly from what I understood from the MPL license, it means
> that any modification to them should always be released under MPL
> license.

This is true of *many* licenses -- GPL, LGPL, CPL, all of which are more
commonly used than the MPL (I know of only one project using the MPL,
and Mozilla is triple-licensed anyway).

> My objectives with these assemblies are:
> * garantie that these will always be open and that no entity can close
>   it under a proprietary form
> * allow the development of closed source applications, retaining the
>   fact that those closed source applications only link the MPL
>   assemblies (inherit from classes or implement defined interfaces), but
>   do not change them
> * allow the development of opensource applications
> * I do not want to retain (or have assigned to me) copyright by
>   possible external developers, meaning that there will not be a
>   licensing scheme like mySQL.

The LGPL would permit all of this, and is more commonly known.

For a better analysis, consult the debian-legal archives:

	http://lists.debian.org/debian-legal/2004/06/msg00221.html

All told, I would suggest *not* using the MPL.

> My questions are:
> * Does MPL license allows this situation?

Probably, but I'm not a lawyer either.

> * By using MPL license does that mean that the only thing I can not do
> is use others GPL code?

Bwa-ha-ha-ha-ha-ha.

Uh, sorry.

The only thing you CAN do, *ever*, is comply with the licenses of
others.  Period.  (And if you can't do that, then you can't distribute.
Period.)  If you don't use anyone else's code, you can choose any
license you want, but you may restrict what others can do with your
code.

The way you phrased it, you could copy leaked Microsoft source code into
your app and be fine ("...the only thing I can not do...").  Ditto for
CPL, Apache, BSD, Apple, and other licenses.  You must always follow the
terms of the code you use.

> * Would be a good choice to appy a triple-license (MPL/GPL/LGPL) to
> these base assemblies so in the future the MPL license would not be a
> limitation to possible development of (GPL) products based in these
> assemblies?

If you choose to use the MPL, a dual license MPL/LGPL should permit GPL
code to use your code.

 - Jon