OK guys, you all have given great feedback and I have also continued my own research on these bills. I have decided to post 25 or so on ebay, but I have run into something else I do not understand. I checked all the serial numbers against the known fakes, as suggested, and they have all turned out to be authentic. However I have one $5 bill dated April 6th 1863 that has no serial number!! the line where is should be written is there, but the number itself is not. So before I post this one I have to ask, what does this mean? Is it worthless without a serial number, what is going on here?!