Question with those with a bestbuy product replacement plan

My cousins 360 passed away thanks to halo 3. My question is i have a prp at bestbuy. I want to know does bestbuy gather your serial # on initial purchase? I don't see it anywhere on the receipt. I also heard they only start using the serial # after the first return. So obviously if they do it that way i couldn't help my cousin out. Thanks fellaz.

Yeah i read between those lines thanks a lot my friend.