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Maybe it has a short TTL? So it would catch a group of people that all bought fake IDs from the same place.

Generally it's configurable. The one that comes to mind first is TokenWorks's Anti-Passback feature which says "Set your custom timeframe (1 hour to 7 days)"

https://www.idscanner.com/product-features/anti-passback/

All except the first person to get through. :)

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