Originally Posted by
fly18725
If a passenger's boarding pass was scanned by the TSA, e.g. mobile or Pre-Check, the airlines are able to see if the passenger cleared security, but to my knowledge, not when.
Do you have any citations for this? This is the first time I've heard of anything like it in the US. Also, re: paper BPs: every time I used a paper BP during this holiday travel, the BP was scanned at the checkpoint. Precheck wouldn't work without scanning, because someone could just photoshop a PC logo onto their BP (any other issues with TSA notwithstanding).