The C++ sources for QuteCsound are licenced under the LGPLv2.1 licence. See the file lgpl-2.1.txt for more details, or visit http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.

The opcodes.xml file comes from the Canonical Csound Reference Manual, which is hosted at sourceforge (http://sourceforge.net/projects/csound). It is licenced under the GFDL (GNU Free Documentation Licence http://www.gnu.org/copyleft/fdl.html).

The icons inside the application come from the gartoon collection (see http://http://commons.wikimedia.org/wiki/Gartoon_icons) and are licenced under the GPL.
The QuteCsound icon was made by Daniel Prieto and it is licenced under the Creative Commons Attribution-Share Alike Licence.

The Python snake icon pyroom.svg by Andrew is licenced GPL, downloaded from: http://wiki.pyroom.org/doku.php?id=visual_identity