Public License Q ( QPL ) is a non- copyleft license created by Trolltech for its free edition of Qt . It was used until Qt 3.0 when version 4.0 of the Trolltech toolkit was released under GPL version 2.
It violates the Debian criteria for determining the open source software [1] used by several Linux distributions , although it qualifies as a Free Software Foundation Definition of Free Software; be that as it may, it is incompatible with the FSU GNU General Public License , [2] which means that products derived from the code under both licenses — the GPL and QPL — cannot be distributed.
Content
- 1 History
- 2 Compatibility
- 3 See also
- 4 References
- 5 External links
History
KDE , the desktop environment for Linux , is based on Qt. Only the personal version of Qt was distributed under QPL; the commercial version, functionally equal, was licensed for use and could not be freely distributed. Meanwhile, the Free Software Foundation and the authors of the GPL objected to QPL as a non-copyleft license incompatible with the GPL. [2] As KDE gained popularity, the free software movement encouraged Trolltech to post Qt under a license (QPL) to ensure that it remains free software forever and can be used and developed by third-party commercial parties. In the end, under pressure, Trolltech provided the opportunity to use Qt under the terms of one of two licenses: either the GPL or QPL.
Compatibility
All legal disputes over a license are pending in Oslo , Norway , but this has never been challenged legally.
See also
- Open source license
Links
- ↑ "Re: Bug # 251983: libcwd: QPL license is non-free; package should not be in main" . debian-legal mailinglist . June 8, 2004.
- ↑ 1 2 "Various Licenses and Comments about Them . "