[mythtv] Trolltech To Extend Dual Licensing to Qt for Windows
Joseph A. Caputo
jcaputo1 at comcast.net
Mon Feb 7 15:31:56 UTC 2005
Just got this in my inbox, thought some folks here might be
---------- Forwarded Message ----------
Subject: Trolltech To Extend Dual Licensing to Qt for Windows
Date: Monday 07 February 2005 9:51
Dear Qt User/Qt Customer:
Trolltech is pleased to announce that we intend to make Qt 4 for Windows
available under our successful dual licensing business model. This
means that Open Source projects under the GNU GPL license will be able
to target all major operating systems using Qt 4. We plan to release the
Windows Open Source version of Qt at the same time as Qt 4.
What dual licensing means
Qt's dual licensing model is based on the principle of fair exchange. If
you are using Qt commercially - that is, for creating proprietary
software for sale or use in a commercial setting - you must purchase a
commercial license from Trolltech. Alternatively, if you wish to write
Open Source software you can use the Open Source version of Qt, released
under the GPL. If you use the Open Source version you must release your
application and complete source code under the GPL as well.
This model has proven successful for a number of leading companies such
as MySQL and Sleepycat, and has been important to the success of Qt on
the X11 and Mac OS X platforms. For more information on Trolltechs dual
licensing business model, visit
What this means for Trolltech customers
The need for customers to hold commercial licenses for all commercial
development will not change.
However, the extension of the dual license model to Windows will mean
that both the pool of available talent and the number of innovative
Qt-based applications on Windows will increase. Also we expect that Open
Source users will contribute valuable feedback and quality assurance for
the Windows version of Qt, just like our X11 and Mac users have in the
The commercial version of Qt will contain a number of product elements
that only commercial license holders will have access to, including:
- Trolltech support
- The opportunity to purchase access to Qt Solutions
- Commercial compiler support
- Prebuilt Qt binaries (the GPL package is source only)
- Commercial database drivers
Finally, we believe that Open Source users who have been exposed to Qt
will choose the commercial version of Qt for their commercial work, thus
boosting Trolltech's revenue and making more resources available for
development and improvement of the product.
What this means for the Open Source community
The Open Source movement has contributed huge amounts of innovative,
highly useful software. Numerous well-known Open Source projects such as
Apache, Mozilla/Firefox and KDE have helped redefine the landscape of
computing and have propelled Open Source from a niche phenomenon into a
By making Qt available under the GPL license on Windows, Trolltech has
given cross-platform Open Source projects the option of jump-starting
their Windows development, using a mature, feature-rich framework that
is consistent across platforms. Open Source developers can spend more
time developing and refining functionality and less time on fixing and
debugging underlying architecture.
How Trolltech will enforce licensing
We depend on revenue from the commercial version of Qt in order to
develop and enhance new versions. It is therefore imperative that users
of Qt understand our licensing and choose the correct license for each
project. To determine which license you require, please visit
http://www.trolltech.com/products/qt/licensing.html, or contact a
Trolltech representative directly.
We kindly request our customers and users to ensure that they are in
possession of the appropriate number of commercial Qt licenses.
It is possible to find out if an application has been created using Qt.
Trolltech is prepared to take steps against misuse of the Open Source
version for commercial development.
Availability, timing and further information
We plan to release the Windows Open Source version of Qt at the same
time as the final release of Qt 4.0.
For more information, please refer to the Windows Dual Licensing FAQ on
The Trolltech Team
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