Found iPhone 5, Can i use it?

If i currently have a Sprint Galaxy S 3 and i found a iPhone 5 for Sprint also, is it possible for me to go to Sprint and get them to switch my phone over to the iPhone 5 instead of my Galaxy?

The owner will have reported it lost or stolen, and the serial number will be barred from activation.

Right now yes because you can change the sim and do a factory reinstall. However once IOS 7 comes out people wont have as easy of a time using a pre owned iphone.

If it gets reported stolen the phone will be useless on any carrier and you could get in trouble.
if you need a legit iphone 5, email me i have a few for sale or trade.