from what I heard bills with the security features covered are removed from circulation. I would imagine that they have to be pretty damaged as well cause I cannot see them being destroyed just for that. Avoid those shiny places on the bills, or the places that when you hold them up to the light you make a complete number or something. Or a head shows up etc. I will see if I can find the scanned page of other peoples marked bills for you. If not then we just holler "Pooga" and he does it. :o)