All Murphy source code files are licensed under the three-clause BSD
license. See file LICENSE-BSD for the license text.

It is possible to configure Murphy to use GPLv2-licensed libraries. At
least libdbus is licensed under the GPLv2, and under some circumstances
PulseAudio client library might also fall under the GPLv2. If Murphy is
configured to use these GPL-licensed libraries, Murphy must be
distributed under the restrictions defined in GPLv2 license text.

To prevent mistakes in licensing, Murphy needs to be configured with
--enable-gpl configuration option in order to use the GPLv2-licensed
libaries. This is meant as a heads-up for the system integrator to
double-check the licensing and distribution of possible proprietary
Murphy plugins.