The license for Geogebra says:
- You are free to copy, distribute and transmit GeoGebra for non-commercial purposes. Non-commercial use is subject to the terms of our GeoGebra Non-Commercial License Agreement.
- Any use of GeoGebra for a commercial purpose is subject to and requires a special license. If you intend to use GeoGebra for a commercial purpose, please contact [email protected] to arrange a License and Collaboration Agreement with us.
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Non-commercial License Terms
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- The GeoGebra source code is licensed to you under the terms of the GNU General Public License (version 3 or later) as published by the Free Software Foundation, the current text of which can be found via this link: http://www.gnu.org/licenses/gpl.html("GPL"). Attribution (as required by the GPL) should take the form of (at least) a mention of our name, an appropriate copyright notice and a link to our website located at https://www.geogebra.org.
Aren't these "GPL for non-commercial use only" terms essentially void? If the give me, a non-commercial Geogebra user, a version of their software under GPL3, then I can re-release it under GPL3 to the rest of the world without all other restrictions, making it available under GPL3 for commercial uses as well.