Open source licenses provide the basic legal tools used by developers to overcome barriers to collaboration and improvement imposed by copyright law. This talk will give an overview of some of the more interesting legal issues around the current state of open source licensing. We will address the purported decline of the GPL and copyleft, the apparent trend of 'post-open source software' (public source repositories with no explicit license), the use of open source licenses to deal with software patents, and the controversy over projects requiring contributions to be made under non-open-source CLAs.