Switching iPhone 4S to iPhone 4S

[wechelle]

I tend to switch phones a lot, whether it is because I'm bored with a color, I put the most minute scratch on it, a friend wants to sell their better model, etc. As an AT&T customer I could just buy whichever iPhone I wanted and pop my sim into it. My understanding for Verizon is that a phone must have a clean number of some sort to indicate it is not lost or stolen. Now that the iPhone 4S is the same for all carriers, it got me to thinking. Can a phone be technically considered lost or stolen by Verizon, but still work for AT&T or Sprint? I'm just curious about how that all works since I will likely switch phones as I have in the past. I'd hate to buy a phone that Verizon thinks is stolen and it won't work for me on AT&T.