What software license do your Joomla extensions use?
The license under which our Joomla extensions are distributed is the GNU General Public License, version 3 from the Free Software Foundation. A copy of the license is included with every Joomlatools extension, but you can also read the text of the license here.
Part of this license outlines requirements for derivative works, such as plugins or templates. Derivatives of Joomlatools code inherit the GPL license. There is some legal grey area regarding what is considered a derivative work, but we feel strongly that plugins and templates of Joomlatools extensions are derivative work and thus inherit the GPL license.
Please see http://www.gnu.org/licenses/gpl-faq.html for more information on the GPL license.