In order for a note to be a "Birthday Note" do all seven numbers have to be used in the date? I would say yes. The example used by Punky's Dad (#1311962) is either Jan 13, 1962 or Jan 31, 1962. If you have a banknote that say has the serial number 5691967, I would think that this would NOT be a Birthday Note because only 4 of the 7 numbers are being used. I have seen some banknotes on eBay with a similar number layout where you only have the year, yet they are saying that these are Birthday Notes. Any opinions?