The original QCad code, downloaded from http://www.qcad.org/qcad_downloads.html, is licensed GPLv2,
 which can be seen in the file gpl-2.0.txt. Copyright is predominately Andrew Mustain/RibbonSoft, but see
 individual files for copyright information.

New code, additions/edits to the QCad code base are Copyright 2010-2011:
R. van Twisk <ries@vantwisk.nl>
Rallaz <rallazz@gmail.com>
Dongxu Li <dongxuli2011@gmail.com>
Claude Sylvain <csylvain@electro-technica.com>
Scott Howard <showard@debian.org>
Lisandro Damián Nicanor Pérez Meyer <perezmeyer@gmail.com

The new code, additions/edits to the QCad code base are licensed GPLv2 or any later version. The text of this
 license is stored in gpl-2.0greater.txt.

WenQuanYi fonts (wqy-unicode.lff) are covered by Apache2 or GPLv3, the text of which is in the base directory.

Additional information is in the header of each source code file.