Subject: Re: I give up...
From: Arnoud Engelfriet <>
Date: Fri, 21 Nov 2003 17:17:02 +0100 wrote:
> Arnoud wrote:
> > ...release it under the GPL ... (and keep it) proprietary in the internal
> project...
> > Of course you cannot ever use any modifications from the external,
> > GPL-licensed project in your proprietary internal project.
> > How will your company benefit from the release as open source?
> We want to benefit from the modifications and support made by the
> community. That is why it should be under one license only.

If your code is incorporated in a GPL-licensed project, and
people make modifications in the project, you *cannot* use
these modifications in a proprietary product. 

> >From the replies, I gather that the BSD, MIT and ZLib licenses are the same
> ???

BSD requires you to publish certain notices in the documentation
if you do a binary-only release.

MIT requires you to keep the notices in the source intact.

zlib/libpng forbids you from saying you wrote that software
if you didn't.

All are GPL-compatible. That means, anyone can take this code
and combine it with GPL-licensed code. If the result is
distributed, it must be distributed under GPL. Hence modifications
to the distributed code will also be under GPL. You then cannot
use the modifications in your proprietary software.

> Does any of these protect against someone taking the source and making
> their own proprietary version, without recognizing the developers that
> built it?

No. For that you want the LGPL, Mozilla PL or the GPL.
BSD requires acknowledgements, but that's it. 

> I suppose giving full freedom to my company, also gives it to others like
> Microsoft?

You are free to use your own code however you want. You can
keep it proprietary in one product, and release it under GPL
with another product. You can make modifications to the proprietary
version without having to release those in the GPL version.

What you can *not* do is take other people's improvements and
put them in the proprietary version, unless you have their
permission. Licenses like the LGPL and GPL require
contributors to give permission, but then you can only use
those contributions under those licenses.

You could draft a license that makes software publicly available
under open source conditions. You can then add to that license
that you must be given the right to use everyone's modifications
any way you want. This however is not very popular with the
community and you will not attract many developers willing to
modify your software.


Arnoud Engelfriet, Dutch patent attorney - Speaking only for myself
Patents, copyright and IPR explained for techies:
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