On Mon, Nov 3, 2008 at 6:42 PM, Ronan Paixão <[EMAIL PROTECTED]> wrote:
>
>
>> Qt was originally licensed under terms which many people considered
>> not open source or not GPL compatible. I think a consequence of this
>> was that the GNOME project took off in order to develop an alternative
>> to the KDE desktop environment, which originally was developed with Qt
>> using the above licensing terms. Fortunately (to me, at least),
>> Trolltech revised the licensing terms and now Qt is GPL compatible.
>> You can say that there's only one version of Qt, that's the open
>> source version. If you use Qt in an open source project (that's GPL
>> compatible), then you don't have to pay any cash to the company that
>> owns the copyright to Qt. However, the same open source version of Qt
>> can also be covered by a business license. This means that if you use
>> Qt in a closed source, propriety product and you plan to distribute
>> that product for royalties, then legally you must obtain a "business"
>> license from the company that owns the copyright to Qt (translation:
>> pay the dough to get the go).
>
> I've talked to a friend which works for a big company that uses Qt with
> the commercial license.
>
> He said that, even though one making patches to the GPL version might
> think that code is also GPL'd, Trolltech has the right to use that patch
> as part of Qt distributed with the commercial license.
I think you are completely confusing software licenses and copyright
here. If you look at the Qt license it starts:
TROLL TECH FREE SOFTWARE LICENSE
Copyright (C) 1992-1997 Troll Tech AS. All rights reserved.
See, e.g., http://www.kde.org/whatiskde/licenses/LICENSE/.
This means that anything included with Qt is copyright by
TrollTech. Thus presumably anybody who submits a patch
for inclusion in Qt must sign over their copyright. At this point
Qt can do anything they want with said code. This is a pretty
common policy, e.g., the GMP library has a similar policy,
as do *many* FSF projects and other projects like Python.
The Linux kernel is a noticeable exception because contributors
do not have to sign over copyright.
-- William
> He also noticed
> that even though that may seem "unethical" at first, it isn't because:
> 1) Who makes the patch first "takes advantage" of who made the initial
> software;
> 2) Who makes the patch must be aware of that before making the patch, as
> it's also part of the dual-license agreement;
> 3) and most important, if Trolltech thinks the patch worth it, the
> patcher can be hired as a contractor to receive compensation for that
> patch, and to avoid litigation.
>
> So, with that in mind, some stuff I said in previous e-mails may be
> inaccurate (as some in this e-mail may also be, since IANAL).
>
> Ronan Paixão
>
>
> >
>
--
William Stein
Associate Professor of Mathematics
University of Washington
http://wstein.org
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