Gnuplot licence
The Gnuplot Licence is a very restrictive open source software licence believed to have the gnuplot package as its sole remaining user. Note that despite the similar name it has no relation to the to the Free Software Foundation in any way and the package and the licence actually actually predates the use of the GNU name and the GPL license by the FSF by a few years. It is in fact more than probable that both the GNU name and the idea to use a restrictive open source licence originates from the gnuplot package.
Disclaimer
Note that the licence text below is here for reference purposes and unlike other material on the EDM/2 Wiki is not under the Attribution-ShareAlike 3.0 licence and should be treated under its own terms, or if an addition by the combined terms of the addition and the licence that it is an addition to. As it is a licence with fixed terms the text below it should not be modified except for formatting purposes, if a more recent version is published a new page should be created for that licence since software packages that do not get updated will continue to be governed by the terms of the older licence.
Text of licence
Copyright 1986 - 1993, 1998, 2004 Thomas Williams, Colin Kelley
Permission to use, copy, and distribute this software and its documentation for any purpose with or without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation.
Permission to modify the software is granted, but not the right to distribute the complete modified source code. Modifications are to be distributed as patches to the released version. Permission to distribute binaries produced by compiling modified sources is granted, provided you
1. distribute the corresponding source modifications from the released version in the form of a patch file along with the binaries,
2. add special version identification to distinguish your version in addition to the base release version number,
3. provide your name and address as the primary contact for the support of your modified version, and
4. retain our contact information in regard to use of the base software.
Permission to distribute the released version of the source code along with corresponding source modifications in the form of a patch file is granted with same provisions 2 through 4 for binary distributions.
This software is provided "as is" without express or implied warranty to the extent permitted by applicable law.