IANAL, but from what I've read, the original legislative intent, in most jurisdictions, is that the process by which an artefact is created (including a stream

IANAL, but from what I've read, the original legislative intent, in most jurisdictions, is that the process by which an artefact is created (including a stream of bits sent over a network or data sent on a block device) rather than the data itself which makes something a protected work - and it is the process of copying that is restricted. If you invent the exact same sequence completely independently, you own it. However, the problem of looking at data and saying that copying happened is one of inference; if I posted exactly the same comment you just wrote, I could have independently come up with your copyrighted comment, and hence own the copyright, but the much more likely explanation is that I copied your comment, and so judges and juries infer copying from similarity that they believe is statistically unlikely. So if person A generates a random string from the uniform distribution, and communicates it securely to a trusted person, B, who XORs the string with your comment, and A shares the random string with the public, while B shares the XORed string, technically only B commits direct copyright infringement, because B created a derivative work by XORing, and broadcast that work (copying). If done properly, no one could prove which person was A and which was B however. In practice, however, it is likely that if both people acted with intent to distribute the work, they would both be at least secondarily liable.