That's what I don't understand:

> they will assert ownership of anything you do while employed, on or off the clock, using your own equipment or theirs

How can this be legal (or enforcable)? I can see that the work done on the clock, with company equipment, is what they paid for and own. What you do on your own time and equipment though, they haven't paid (and doubt would be willing to pay) to own all of your time and work.

But I've heard it's common - fortunately I've never been in that situation, and would not consider signing such an unfair contract.