The GNU General Public Licence (currently version 2) is the basis of open source software: the licence allows software users to use software free of charge, to copy it and to improve it by making the source code available. However, under the licence, improvements must also be made available on the same basis.
The new draft of GPL v3 is the first since 1991.
GPLv3 will specifically attack Digital Rights Management by prohibiting
the use of GPL-licensed software as part of a DRM system. It also seeks to limit the effectiveness of patents based on GPL licensed software.
Businesses will need to review their use of software based on GPL licences.