"Joint holders can also enforce copyright, though open source codebases work more like collective copyright." Joint copyright is basically non-existent in the

"Joint holders can also enforce copyright, though open source codebases work more like collective copyright." Joint copyright is basically non-existent in the US. For example, you must intend to create a joint work at the time of creation. You can't make it joint later on by signing a document saying it's joint with someone. There are other issues too. This is deliberate, as joint owners each own a 100% enforceable set of rights, and the law doesn't really want tons of people running around claiming to own the same work. "That said, non-exclusive Linux kernel copyright holders have performed enforcement activities (quietly or noisily)..." Not in the US. It's not possible in the US. It'll get dismissed immediately.