How does an anti-shoplifting scanner know if you’ve bought the item?


I read that the scanners at the doors of a store detect items with magnets and such but what I don’t understand is how it differentiates between items that have been paid for

In: Technology

The store has to put stickers or anti shoplifting tags on the items, if bought they are either removed or made to no longer work. If that doesn’t happen scanner will go off.

It’s not all items, it’s high price items that have a tag that gets disabled or removed at the till?

Former retail worker here!

We (at my old job) actually removed them at checkout. Occasionally one would slip past the cashiers and trigger the alarms, at which point one of us would go to the front and remove the tag.

(In case anyone is wondering, my former employer is a retail chain whose name rhymes with Bold Gravy.)

There are stickers they put on products like razor blades, batteries, small items easy to put in a pocket, purse, etc. There is a pad at the checkout the clerk will run the sticker over to demagnetize the sticker. Not sure if big stores use much anymore due to self-checkouts.

they can remove the actual magnet or demagnetize the magnet (ie in book bindings). typically, this can only be done by the cashier, so if you paid for it, you’ll walk out. if you didn’t or the cashier messed up, you’d sound the alarm.