which license to use for software using components with GPL, LGPL and EPL?

Ian Vernon ian.vernon at amanzitel.com
Tue Sep 1 08:25:37 UTC 2009

Dear John,

Thanks for the enlightenment. Now if one wants to distribute its code open
source what is the best choice other than redoing the conflicting parts?


-----Original Message-----
From: John Cowan [mailto:cowan at ccil.org] 
Sent: Monday, August 31, 2009 10:24 PM
To: Ian Vernon
Cc: 'John Cowan'; license-discuss at opensource.org
Subject: Re: which license to use for software using components with GPL,

Ian Vernon scripsit:

> Thanks. The GPL components are derivative works which releases their 
> software under GPL same is true with the EPL and GPL components. 
> Although all external components only comprises less than 5% of the actual
> We would prefer to have the software under GPL, although it seems it 
> is now depend which components are more critical then the license shall

No, it doesn't.  If you use GPLed modules, your work as a whole must be
GPLed, which means that if you distribute it in binary form, you must
distribute it in source form as well.

> another note all licenses seems to be compatible if released as 
> commercial;

Not so.  Commercial or non-commercial (that is, for profit or not for
profit) has nothing to do with the GPL or any open source license.
But you cannot keep the source secret and use GPLed modules.  Nor can you
use EPLed and GPLed modules in the same product, because the GPL and EPL
impose contradictory restrictions on you.

In a word, you have made agreements with two different suppliers, and you
can't satisfy either without breaking your promises to the other.
That's a situation you have to get out of the best you can.  Maybe one of
them will let you off the hook, maybe not.

> having said that, in the worse case the software is forced to be 
> released as commercial instead of open source.

That is not so.  It violates your obligations to the authors of the GPL
modules.  The worst case is that you can't ship at all without replacing
some of your modules by "clean room" equivalents (written without access to
the source code).

> Should it not that the community should work hand in hand to protect 
> copy left instead of developers being burdened with incompatibility 
> issues?

"The community" isn't a single community; it's a variety of different groups
with different agendas.  Dealing with that is a routine matter of business
-- but too late now.

Knowledge studies others / Wisdom is self-known;      John Cowan
Muscle masters brothers / Self-mastery is bone;       cowan at ccil.org
Content need never borrow / Ambition wanders blind;   http://ccil.org/~cowan
Vitality cleaves to the marrow / Leaving death behind.    --Tao 33 (Bynner)

More information about the License-discuss mailing list