Yep, and on the hub. I'd start with a few love taps from a deadblow. If no joy, I'd get the air chisel and hit it at 3 & 9 from the front on the hub and then from the back rotating it as needed to clear the backing plate. Usually a few back and forths and it popped right off.

On one occasion a coworker was going to TOWN taking his anger out on this one seized rotor. He couldn't get it off after 10 minutes. I went over with the chisel and had it off in 30 seconds. The rapid fire blows work better than strong blows from a sledge (like an impact gun works better than just heaving on a wrench).