Originally Posted by
ridefar
I would assume by boarding pass. You have to show a BP for your US arrival departure, and a BP for your onward destination in Canada. They already use this approach for the separate transit area for pax with security and customs.
That completely defeats the purpose of OSS.
If Alice from Chicago and Bob from Shanghai are walking down the same hallway, he can slip something in her pocket/bag/whatever.
Then she doesn't clear security, and he does. Then she gives it back to him.