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.


Non-commercial License Terms


  1. 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.

2 Answers 2


The Geogebra license is nonsensical. You are absolutely correct: "GPL for non-commercial use only" is an impossible combination. The GPL specifically forbids the imposition of any additional licensing restrictions on top of the GPL:

You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License.

Furthermore, the GPL specifically states what happens when anyone attempts to impose additional restrictions on GPL software:

If you cannot convey a covered work so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not convey it at all.

The Geogebra license itself also states:

This License incorporates (by reference) additional license terms published by the Free Software Foundation and the Creative Commons Corporation. In the event of any conflict between those additional terms and the terms of this License, the latter shall prevail.

Since there is indeed a conflict between the Geogebra license and the GPL, the Geogebra license prevails, and the GPL is inapplicable.

There is one further complication. Geogebra is free to invalidate the GPL with respect to their own software for which they own the copyright, but Geogebra is absolutely forbidden from incorporating third-party GPL software into their own codebase and distributing that codebase under non-GPL licensing terms. Doing so violates the GPL, because the GPL forbids the imposition of additional licensing restrictions, as highlighted above. Unfortuantely, this situation is relevant, because Geogebra includes third-party GPL software, for which the Geogebra Group does not own the copyright.

From a legal standpoint, Geogebra is violating the GPL by distributing third-party GPL software under non-GPL terms. If they were to fix this licensing violation by removing said third-party software, then Geogebra would be non-GPL freeware, licensed only for non-commercial use without a paid license. The portions of the Geogebra license claiming that (portions of) Geogebra are GPL are invalid and void.

It is worth noting that Debian only distributes version of Geogebra, from 2013, which was unambiguously licensed under the GPL and pre-dates the current nonsensical license.


This won't work in the United States. In the United States, if you own a lawfully-made copy of a work and haven't agreed to any particular restrictions on it, you are permitted by law to do anything that isn't reserved to the copyright holder. What is reserved to the copyright holder is specified by 17 USC 106, and ordinary use of the work is not on that list.

If you buy a book, or find a book, or otherwise come to lawfully possess a book, you can read that book. It doesn't matter if the book has a license page that says you agree to only read the book on Sundays, because you don't have to agree to a license unless you want to.

Or worse, imagine if somebody drops copies of their poem from an airplane and on the back of each poem is printed a "license" that claims you agree to certain restrictions on what you can do with the poem if you read it. That's not enforceable because nobody needs to agree to the license to read the poem. They can read the poem because they own the paper it's on. Ordinary use is not a right restricted by copyright and nobody can make you agree to something to let you do something that you already have the right to do.

By right of possession, you may do anything the law doesn't restrict to the copyright holder, and that is not ordinary use in the United States.

You don't need a license to read a book you own. You don't need a license to use a piece of software you own.

  • 1
    The question is not about simply using a piece of software but about redistributing it, something that a license on the back of a poem dropped from an airplane very well could regulate.
    – jwodder
    Commented Jul 23, 2020 at 4:07
  • @jwodder The questions says, "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.". It's about a license that restricts non-commercial use, which a license cannot do in the United States. Commented Jul 23, 2020 at 4:21
  • @chrstphrchvz We aren't talking about EULA's here. An EULA is a contract that you must agree to in order to use the software that is binding on all those, and only those, that explicitly agreed to the EULA, see ProCD, Inc. v. Zeidenberg. The burden is on the person who seeks to enforce the EULA to prove agreement to the EULA using something like a click-through or shrink-wrap agreement. It has no relevance to licenses like the GPL which don't have such things (or, if they do, anyone can remove them since the GPL allows it). Commented Jul 30, 2020 at 17:39

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