On 30 April 1993 CERN issued a public statement stating that the three components of Web software (the basic line-mode client, the basic server and the library of common code) were put in the Public Domain with the statement:
It was the early ’90s and concepts like free and open software and public domain were in their infancy. Richard Stallman had created the Free Software Foundation, launched the GNU project and written the GNU General Public Licence (GPL). He was already evangelising the computing community, recommending protection of software by keeping ownership to guarantee its free use.
Open Source release
In summer 1994, Tim Berners-Lee left CERN to create the World Wide Web Consortium (W3C) at MIT. François Flückiger took over his technical team at CERN. At that time, the team was preparing the release of version 3 of the CERN server software, WWW (HTTPD).
By that time, the Free Software movement had become more active, better known at CERN, and the risks of appropriation were more clearly described, in particular by Richard Stallman and the GNU project. Flückiger evaluated various options with CERN’s Legal service and decided to release the new version as Open Source – CERN would retain the copyright to protect the software from appropriation as well as to secure attribution, but would grant to anyone the perpetual and irrevocable right to use and modify it, freely and at no cost.
On 15 November 1994, Flückiger sent the following message to the Web community:
The first CERN Open Source software licence
CERN developed its own open-source licence to accommodate the laboratory’s legal status as an international organisation. The licence had two main threads: copyright and free use.
CERN opted for a fully permissive open-source licence. This meant that the licensees had the right to release derivative works under a licence of their choice, provided they perpetuated the statement attributing the credit of the initial work to CERN:
MIT Open Source release
In 1995, the W3C was established at MIT. It was later complemented with a European Leg at the Institut de Recherche en Informatique et Automatique (INRIA). While v3.0 of the Web was the first release by CERN of Open Source software, it was also the last release by CERN of any Web software – the ball was now in the court of the W3C.
In July 1995, MIT released version 3.1 of the WWW (HTTPD) software, based on the CERN version 3.0. Just as CERN had done six months earlier, an MIT-specific licence was chosen, close to the CERN one. It was also a fully permissive licence.
Since then all the subsequent versions of the Web software released by MIT were Open Source. They always faithfully reproduced the CERN credit notice. The attribution issue had been satisfactorily addressed by the first CERN-specific licence.
Towards “Copyleft”
By adopting an Open Source policy in ’94, CERN had made a significant step towards better understanding the mechanisms for freely distributing its software. But we were still learning and the maturing process was not over yet.
Indeed, a few years later we started to appreciate not only the power but also the risks of a fully permissive licence that allows derivative works to be distributed under a different licence. Even though a fully permissive licence was a powerful incentive for dissemination of CERN software, it held within it the seeds of more subtle forms or appropriation, and more importantly, did not provide the necessary incentive for what was later called “collaborative dissemination”.
Collaborative dissemination is the creation of open communities of users who are invited to improve and complement the software and share their enhancements with the community. The vehicle for this is not a permissive licence as it does not encourage the licensees to reinvest their improvements in the community. The appropriate vehicle is Copyleft licensing.
The philosophy of Copyleft licensing is as follows:
Since an Open Source user receives the source of the software, then the user must, in turn, provide the source of any modified version. As a derivative work must be distributed under the same licence, Copyleft licences are said to ensure the non-appropriation by third-parties of the Open Source software.
Standard Form Licences
Copyleft licensing is now the recommended and most frequently used means for freely and openly distributing CERN software. But rather than continuing to write our own licences, we turned instead to standard form licences certified by the Open Source Initiative (OSI) authority, such as GPLv3. We realised that the importance of having a licence whose spirit is instantly recognisable and whose terms are familiar outweighed the desire to tailor terms which make our status clear. This was the way to maximise re-use!
Like our research at CERN, this also was a journey of discovery. We had to learn, and this learning was largely achieved through the most famous of all CERN software, the one that changed the face of the world.