My personal thought is that all pieces of crossfire should be under the GPL. This includes images, maps, code changes, etc. I have several reasons: 1) Consistency with crossfire as a whole - having a potentially large number of images/maps/whatever with different policies would prove very annoying. Just trying to notify people that this image is restricted but that is not. Could you imagine if this was the protocol with some xpm images when we converted them to png? In theory, we would need to require the authors permission for that. 2) Consistency with open source principals. It seems at least somewhat possible that if people can attach limitations to what they contribute, more people may do so. I can't give precise examples, but I am sure crossfire has borrowed various pieces from other open source applications - it would be somewhat facetious to do that and say other people can't use pieces of our software. I would also have to check, but sourceforge may have rules about what they host (eg, opensource applications, and not those with specific redistribution rules) 3) Maintainability - if you have to check with people to make changes, or even need to check various files to see if something might be encumbered, it could prove to be a real pain. I would also thing that some aspects of his copyright would be highly suspect. Is use allowed in the client? Suppose someone makes a different server, which is a pay per server, but uses a compatibile client protocol? For those reasons, I really think anything in CVS should be under GPL. Now you could very well have some sets of maps or images with more restrictive rules that people could download if they want to.