Re: [AMBER-Developers] Linking Amber and AmberTools together--GPL issues?

From: Timothy Giese <>
Date: Sat, 5 Nov 2011 12:39:47 -0400

On Sat, Nov 5, 2011 at 12:28 PM, Ross Walker <> wrote:
> Hi Tim,
>> So, anything that anyone adds to AmberTools under the guise of the gpl
>> is automagically licensed under something else as well?  If you owned
>> the copyright - you can change the license however you want - sure.
>> But if a gpl code is accepting contributions without a copyright
>> contract from contributors, then you wouldn't seem to have the right
>> to dual license those contributions.  I would have guessed that the
>> point of gpl-ing ambertools would be to avoid the headache of dealing
>> with that legal headache.
> I believe the assumption is that by contributing code to the AMBER project
> (AMBER / AMBERTools) one is either assigning the copyright to the AMBER
> project or if one signed a non exclusive contributor agreement then one is
> assigning the AMBER Project a specific irrevocable license to use that code.
> Such contributions would precede one making their code GPL or whatever
> license they choose and so would override and invalidate that license within
> the context of AMBER. If one does not agree with these terms, and insists
> for example that their code be strict GPL and thus limit the way it can be
> used in other parts of AMBER (due to licensing differences) then I think is
> not appropriate for that person to contribute to AMBER and thus benefit from
> the distribution vehicle that AMBER represents.

I think I didn't get my point across - if someone created a tool that
used a library and that library was gpl - and I contributed my tool to
amber tools. I don't care about MY copyright. But by having a
contract that says "I have the authority to give you the authority to
dual license" - that can be important information to know. If I don't
own the copyright to that library that my tool uses, then I can still
put it into a gpl ambertools - that's ok - but ambertools would not
be able to be dual licensed. Make sense?

But if the strategy was to reject all code from ambertools unless
everything in it was a less restrictive license than GPL (like mit or
bsd) then gpl ambertools wouldn't itself be prevented from being

Just glancing over the AmberTools/LICENSE, it looks like that's what
was done. - but I think we emailed at the same time.


AMBER-Developers mailing list
Received on Sat Nov 05 2011 - 10:00:05 PDT
Custom Search