This is the free software license for Qt version 1.31; it mainly covers development of free software for the free software community. We believe that it does not constrain development of free software noticeably. (Write to us if you feel hampered, and we may be able to do something about it.)
The professional license is much less restrictive than this one.
Copyright © 1992-1997 Troll Tech AS. All rights reserved.
This is the free software license for Qt version 1.31; it covers private use, use of third-party application programs based on Qt, and development of free software for the free software community.
The Qt toolkit is a product of Troll Tech AS. This license is limited to use with the X Window System.
You may copy this version of the Qt toolkit provided that the entire archive is distributed unchanged and as a whole, including this notice.
You may use this version of the Qt toolkit to compile, link and run application programs legally developed by third parties.
You may use the Qt toolkit to create application programs provided that:
If you are paid to develop something with Qt or it is a part of your job the following conditions also apply:
You may also use the Qt toolkit to create reusable components (such as libraries) provided that you accept the terms above, and in addition that:
[Your package] requires the Qt library, which is copyright Troll Tech AS. Freely distributable programs may generally use Qt for free, see [README.QT] for details.
Troll Tech AS makes no obligation under this license to support or upgrade Qt, or assist in the use of Qt.
In no event shall Troll Tech AS be liable for any lost revenue or profits or other direct, indirect, special, incidental or consequential damages, even if Troll Tech has been advised of the possibility of such damages.
QT IS PROVIDED AS IS WITH NO WARRANTY OF ANY KIND, INCLUDING THE WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
(The FAQ contains a number of questions related to the license.)