At DEN, the ID and BP checkers before security use a little stamp on your BP after they've "verified" everything...at most other airports Ive come across, the checkers simply look at the ID and BP and then wave you through without marking up the BP in anyway...(though when I do think about it, I do remember having my BP marked with pen at security at 1 or 2 places, but I cant remember off the top of my head)...anyways, the point is, whats the significance of the stamp?? It clearly isnt a TSA thing, so does it have any purpose at all???

Thanks,
N674UW

-I wasnt sure if this would be appropriate for here or Travel Safety/Security, since this is a security question but its specific to one airport, feel free to move it if you think its better placed over there mods...thanks!