Most employment agreements are such that the company owns it even if it is outside of normal hours. So inventions you come up with on your own time are not yours.
Ummm, [citation needed] here, I think.
I can't imagine how this is possibly legal, even if it was in there. Yeah, if you use *company provided assets* to develop your invention, sure. You're using their stuff to do it, so they could reasonably argue they should own it (or at least part of it). But if I use my own time, my own assets, my own learning, and it's not even related to my work (e.g., they can't claim that I'm using knowledge learned on the job or something, I could see them trying to argue that), how could they possibly claim it is theirs?
It'd be interested in seeing examples of this, as well as any related court cases where it was upheld. I seriously cannot see how it's possible. I don't know anyone in that boat, nor have I heard of anyone in that boat, nor have I ever seen a contract that tried to say that. And I've seen legal stuff that prevented some related issues, but where the company had a bit more of an argument (non-compete sort of stuff). Not saying I agree with the non-compete stuff, just that it seems like a slightly more rational argument than "anything you invent, regardless of how, where, or when, is ours")