I have just changed the software license of BigBang from GPLv2 to AGPL-3.0.

Soon, I won't have the ability to make such a decision unilaterally. This sort of decision will only be made by community agreement. You may all soon decide to reverse this decision and if so I won't block the change.

However, I wanted to "nudge" the project in this way and explain my reasoning.

When we started the BigBang project years ago, we had to address the question of software licensing. For Free Software principles, I wanted to copyleft the software. This got push back from some potential contributors in industry and people interested in partnering with the project commercially.

In the end I decided to stay with the GPL license because of a project mission that is related to Free Software: the educational mission of open and reproducible research. One reason to build BigBang is to create a platform for data science education that is available to everybody. Open data from the projects that around foundational to the Internet, including standards and protocols, as well as software, are part of the historical record of how our world has become what it is. As much as any legal or cultural history, an understanding of this technical history is essential to our competence as world citizens. It is our shared inheritance. BigBang is designed to make this technical history available to scholars and students in the interest of an informed digital citizenry.

The GNU copyleft philosophy is aligned with this educational mission. My hope is that as contributors to BigBang, we will be conscious of our work being a contribution to global, civil, and collective self-understanding. This self-understanding cannot be proprietary; it must be held in common. GNU licenses prevent "forks" or downstream development work on the project from being incorporated into proprietary systems. This will give us peace of mind: our work will be harder to coopt for the kind of private interests that would make our civil understanding of technology even more difficult.

We met an obstacle early on in committing to these goals through our software license. This project began at UC Berkeley. And while Berkeley has a long history of contributions to open source software, we discovered that it was not an environment compatible with Free Software principles. I have to give Nick Doty tremendous credit for his patient navigation of Berkeley's bureaucracy to get an answer to some questions about intellectual property. Among his findings were that Berkeley permits use of GPLv2, but forbids use of GPLv3. This is most likely because Berkeley would like to reserve the right to patent software created by its students, even if that software is originally licensed open source.

Therefore one of the motivations for moving the BigBang project to DATACTIVE infrastructure is to position the software as a project of the University of Amsterdam, rather than of UC Berkeley. I have to ask our contributors from UvA to follow up on this point. But my hunch is that UvA is less aggressive about defending its privilege of software patenting than UC Berkeley.

As the likelihood of Berkeley making any claim to patent contributions to BigBang is in fact quite low, I must admit that this change in licensing and the timing of it is perhaps as much a symbolic gesture than a substantive one. Putting the project under the auspices of DATACTIVE is in more ways than one a commitment of this project to the public interest. It may even be a way of steering the project towards a more European vision of the public interest than a Californian one. All these questions will ultimately be up to the community to decide.

Thanks for your patience with this long email. More information about GNU licenses can be found here: