Sandy - If you found 5 million in used notes in the street, I doubt it would be the law tracking you down to arrest you but a well resourced criminal organisation; and they would not be looking to put you in prison.
Absolutely definitely if it was a huge multinational bank corporation.
The same would go for any massive globalising business corporation.
If -for example- McDonalds or CocaCola made a multi-million pound clerical error in my favour I would delight in running away with the money.
I'd take the most stringent steps to make sure I wouldn't get caught, then I'd probably take it to India or Nepal and set up some sort of intermediate technology organisation to help the poor.
...so there :-p
I could have got away with a couple of million or so thirty years ago, without it showing up for 8 months, as there was no internal control whatsoever on the issue of shares, for which I was solely responsible.
When I pointed this out at a board meeting, they said "yes, but you wouldn't do it, would you?"
I wouldn`t run. £11,000 was mistakenly paid into my corporate Diners card. I owned up. Diners weren`t very interested and told me to get onto my company`s card services. The woman on the phone told me to wait while she announced to the whole office that I had actually phoned in to confess.
My boss in Belgium in 1983 found that he had been credited Bf 140 million.......(about $3 million). By the time he had realised, he had had the money on his account for 8 days. By the time they resolved it 15 days.
They allowed him to keep the interest - back then that was nearly 1% for a month so £3 million * 0.5% (not accumulative interest) = $15000 (£10k).....not bad for being honest and, allowing for inflation, that's about £40k now.
It does happen though, i work in a building society and once a family came in with £23,000 that they had found when empting her dead mothers house. It was under the carpets and in cereal boxes.