Article snapshot taken from Wikipedia with creative commons attribution-sharealike license.
Give it a read and then ask your questions in the chat.
We can research this topic together.
The German Free Software License (Deutsche Freie Software Lizenz) is a license of open-source nature with the same flavors as the GNU GPL but governed by German law. This makes the license easily acceptable to German authorities. The D-FSL is available in German and in English. Both versions are equally binding.
German court ruled in 2006 that the GNU GPL was indeed enforceable.