1. A friend came across £100 at the auto-teller. She took it inside the bank. No-one claimed it, she got the £100.

2. My wife, some years ago, walked away from the auto-teller instead of picking up the £200 she just requested. When she realised she went into the bank and asked what would happen. She was told if no-one had taken the money it would be sucked back into the machine. So she asked if the money had been sucked back into the machine. "We can not tell yet, but come back in a month" was the reply.

I do not understand the separation of data between the machine and the bank, perhaps between the branch and the machine, but the branch should be able to call somewhere central and find out. Especially for the first example, the customer who is £100 down must have been the previous customer to my friend, how hard would that have been to find out?