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

[John Cowan]

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 software.
> 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 follow.

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)