The site you quoted seems to be something that someone copied & pasted and slapped together. When the author says "32 bill per run", he seems to imply that the

The site you quoted seems to be something that someone copied & pasted and slapped together. When the author says "32 bill per run", he seems to imply that the whole sheet always has the same serial number. Well, it certainly is not always true as you can see in this high-res photo of an uncut sheet of 1985 bills: http://ultrafree.org/graphics/1985-1uncut.jpeg http://ultrafree.org/graphics/1985-1uncut.jpeg A much more informative site which seems to be someone's labor of love says there is an exception with old Nationals "in which all notes on a sheet had the same serial number and had to be distinguished by their plate position letters." Although he's not explicit, my reading of that site suggests that modern bills (including the time of the D. B. Cooper incident) should be unique. [1] http://www.uspapermoney.info/general/number.html http://www.uspapermoney.info/general/number.html