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US patent office confirms AI can’t hold patents
(www.theverge.com)
This is a most excellent place for technology news and articles.
Prior art is still a thing though, and invalidates a patent. I think first to file just means you can't keep an idea secret and then "surprise!, we already invented that be we've been keeping it a secret, but trust us, we were first". If you publish an idea, it establishes prior art and, in theory, prevents future patents of that idea.
Unfortunately I've seen plenty of patents misused exactly as you described. Patent trolls are a thing