The authors of the toolbox, Stephen J. Sangwine and Nicolas Le Bihan, retain copyright in the software and the documentation but grant rights to others under the terms of the licences listed below.
The source code of the Quaternion Toolbox is licensed under the
GNU General Public Licence, currently version 3.
Documentation for the Quaternion Toolbox is licensed under the
GNU Free Documentation License, currently version 1.3.
Copies of both licenses are distributed with the toolbox. They are referenced by the above links, but may also be accessed at the GNU website (see below).