Github has changed its terms of service recently which is potentially very bad for copylefted Free Software. However, views on this are controverrsary and it’ll take some time to clarify the matter in law terms.
- (German) https://www.heise.de/developer/meldung/GitHub-eckt-mit-neuen-Nutzungsbedingungen-an-3647980.html
- https://www.earth.li/~noodles/blog/2017/03/github-tos-change.html
- http://joeyh.name/blog/entry/removing_everything_from_github/
I found the following thread useful as it discusses the matter with some practical examples: http://opensource.stackexchange.com/questions/5193/are-the-new-github-terms-of-service-a-kiss-of-death-for-open-source-projects