Starting with CGAL 3.0, CGAL is available under an Open Source License. More than switching the license, we open up the project and invite you to join. The CGAL project was founded by seven research institutes in 1996, and since, people at other institutions started developing software based on the design ideas of CGAL.
The first step in getting involved is probably to use CGAL. The project provides several mailing lists in order to support discussion within the community. There is also a CGAL Users group on the LinkedIn social network which you may find useful.
The next step is to develop patches or new packages for CGAL. In order to do so, you can take a look at the Developer Manual in order to familiarize yourself with the internal details. You are encouraged to contact us as early as possible when you envision to make a significant contribution to CGAL. Please read carefully the page Contributing to CGAL, which describes precisely the CGAL submission and review process.
You can then become a CGAL developer, which grants you access to the internal ressources like : the developers wiki, the git repository, the cgal-develop mailing list, the internal test-suite, the bug-tracking system, the twice yearly CGAL developer meetings, etc.
The CGAL project can only consider the integration of the software you wrote, if you accept that it is part of the distribution, and if it follows the license scheme chosen by the project. Actually, it is the owner of your code (your employer) who has to agree on this officially. Note that the CGAL project does not require any transfer of intellectual property rights for the contribution of new independant packages, although the situation may be different for a modification to existing code. Moreover, you may choose to have your code also available in the commercial offer of GeometryFactory, which offers various services to customers around CGAL.
To help users and developers to understand the decision processes behind CGAL and how one can get involved, we have written and published the CGAL Open Source Project Rules and Procedures.