Gephi licensing: referendum results

Licences: right to use, modify, sell, integrate...
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Gephi licensing: referendum results

Post by admin » 27 Apr 2011 19:59

Dear everyone,

Following the debate on adopting a new license, a vote by email has been set amongst the source code contributors. They are the legal owners of the Gephi source code:

Cezary Bartosiak
Mathieu Bastian
Julian Bilcke
一杜 (Yi Du)
Mathieu Jacomy
Sébastien Heymann
Patrick McSweeney
André Panisson
Antonio Patriarca
Eduardo Ramos
Martin Skurla
Jérémy Subtil
Helder Suzuki

(Please contact us if you consider that you should be on this list.)

They decided at the full majority (100%) to use the dual licensing CDDL + GNU GPLv3 for the future releases of Gephi.

What does it change in practice?

Dual licensing:
It means the possibility to choose apply either the CDDL or the GNU GPLv3 when Gephi source code is integrated to a derivative work.

If you don't need to modify the files of Gephi source code, then you can integrate it to a product and have the freedom to keep your own sources (new files) private or public and to release the final work in the license you want. If Gephi source code is modified, then only the changes should be published in CDDL+GPL. The CDDL doesn't "contaminate" new files, but files under the CDDL should remain in CDDL and see their changes published.

So this is a major improvement for companies willing to build specific versions of Gephi, targeted to their customers, without the obligation to put their product in open source (they are encouraged, of course ;)). It also unlocks the ability to create derivative work based on Gephi and other code in BSD, so researchers may mix their projects and Gephi without any trouble with funding agencies and partners. Even a Gephi contributor can re-use its code in another project which is under a different license, say the 3D engine integrated in a game published in BSD!

Note that using the Gephi Toolkit as a library will also be allowed whatever the case.

One can build GPL applications based on Gephi.

A plug-in license is independent to the Gephi platform's one.
Plug-ins in GNU (A)GPLv3 cannot be integrated to derivative work not in (A)GPLv3.
Plug-ins can have a commercial license now.

When will this change enter in action?

New licensing will be effective only with the next release of Gephi. The current code is still in GNU AGPLv3.

Copy of the email
Dear Gephi source code owners,

I call you for a _referendum_ on the license of our source code, following the long discussion and trolling on the forum:

To sum up, we always used the GNU (A)GPLv3 to protect our work from a proprietary use. This mechanism is well suited for an end-user software primarily developed for academic purpose. However some major changes raises the question again, in particular:
- Gephi has become not only a software, but a platform to create new applications, integrate third-party technologies, and extend the functionalities with plugins.
- The Gephi Community is diversifying thus starts to include private companies and large research projects.
- We try to reach maturity with more developers and funding supports.

I'm both in contact with companies and research laboratories across Europe and the US. Both reported a strong motivation to use Gephi and to contribute (bug fixes, employment, direct fundings) but are unable to take Gephi because of two typical cases:
- for companies: impossibility to integrate part of Gephi (source code or library linking) in a final product with a proprietary/commercial license.
- for academics: impossibility to integrate part of Gephi (source code or library linking) in an Open Source program with a BSD or MIT license.

The future growth of our community will depend on how we can put them on board. We all have very diverse motivations to contribute to Gephi, but we all do it on our free time. So by this vote, I want to solve these issues:
- How do we reach a broader adoption of Gephi without sacrificing on our ownership rights and the idea of "common good"?
- How to create stable jobs for skilled Gephi developers?
I don't have direct answers of course, however we can shape our ecosystem to enable more opportunities if we choose the right licensing system.

We initially started to oppose xGPL to BSD in the debate but I would like to propose a trade-off that seems to take all your considerations into account: a dual licensing using the GNU AGPLv3 and the Common Development and Distribution License (CDDL). The CDDL is a "weak copyleft" in a sense that every _file_ in CDDL must remain in CDDL, and source code modifications must be published. However one can combine the source code with other licensed code, which is not the case in GPL, LGPL and AGPL. This license is derived from the Mozilla Public License (MPL) and is well recognized by the Open Source Initiative (OSi) and industrials. NetBeans is released under a dual license CDDL-GPLv2 for instance:

The AGPLv3 is no longer required with the CDDL. As this license is hardly understood, we propose to switch back to GPLv3. I must precise that this dual licensing is required because of the incompatibility to statically link code in GPL to one in CDDL. The dual licensing let the developer choose which license he applies. I've just found an accurate illustration on the differences between CDDL and GPL by the way: ... llustrated

- improvements of the source code will remain in open source.
- one can create a specific version of Gephi for his needs with additional files in the desired license.
- using the Gephi Toolkit as a library will also be allowed whatever the case.

The GNU LGPL has a "weak copyleft" only when the code is used as a library. It would be okay for the Gephi Toolkit, but not for building applications over the graphical framework, which hence should be entirely in LGPL.

The dual license would apply to the whole code and not only the part used in the Toolkit. Hence the community will be able to build applications on top of Gephi, like Gephi is on top of Netbeans.

Now the question of this referendum:
Do you agree to release the next official releases of Gephi source code in the dual license CDDL + GNU GPLv3?

Please reply by YES, NO or NEUTRAL to all people in this list and not only me, and add your first name + name in clear after your reply.

You have fifteen (15) days to reply from today. Votes will be closed after that on Tuesday May 3rd at 3pm (UTC+1). Only your first reply will be taken into account; more would mark your vote as "neutral".
Discussions are not allowed in this thread but should stand on the forum.The referendum will be approved only with a full majority (100%) of yes amongst yes+no with at least 50% of the voting participants.

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Re: Gephi licensing: referendum results

Post by mbastian » 27 Apr 2011 20:15

Great job Sebastien on getting this important decision done, and with 100% majority not bad ;)

I'm glad we are doing this, the CDDL is a great license, as it focus only on the source code. No contamination, and no debate about what 'distribution' means. It also give much more freedom for plugin developers, as you mention it. That is great.

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Re: Gephi licensing: referendum results

Post by rockclimb » 18 May 2011 22:39

Thanks for the news. How does this decision affect use of other open source packages? iText5 in particular is AGPL, although the previous version was released under the joint MPL/LGPL, so it's probably possible to modify Gephi to use that version instead.


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