This chapter addresses two licenses closely associated with particular programs: the Q Public License (the Qt Toolkit) and the Artistic License (Perl). Each of these licenses has unique features, reflecting the specific terms that their creators wished to impose on users or modifiers of their work. Unlike the GPL or BSD licenses, these licenses are not frequently applied to programs other than those for which they were originally developed, and they tend to be adapted only for the code originally licensed under them and derivative works. Nonetheless, because these licenses are still in frequent use and because they provide some interesting contrasts to the licenses already discussed, they are described at some length in this chapter.

Also discussed is the Creative Commons license—the fruit of an effort to expand the open source model of development beyond software to literature and the arts. While its creators state that it is not applicable to software, it is a well-written license and has begun what will be an interesting experiment at the very least.