Probably a good thing general purpose AI is still a few decades away at this point. Society is not ready for the rights implications. Not that I really expect people to have better answers to this in the future.
Its not that novel. Take a Corporation it may hire an employee, or contractor - or even unpaid intern - and have them develop copy all day long. That copy will be owned by the Corporation in the future, even if the employee/contractor/intern ceases to work for said Corporation (even if said employee/contractor/intern ceases to exist their work will be owned by said Corporation).
Algorithms are already creating media of all kind (videos, articles, music) and that media is all subject to the same copyright protections as man-made media, replacing algorithm with AI (which seems to be the popular thing to do with SV startups these days, doesn't create Earth shattering facts the law hasn't seen, its just like when the blockchain believers thought DAO code was the law outside the jurisdiction of courts and regulators)
It turns out the AI's conquer humanity not through violence, but by highly optimized IP trolling. Hell, we already have a flavor of this on Youtube, where algorithms flag content all day long with little recourse for innocent victims.