[kingu]

I've noticed of late that cashiers will ask to see my card after I've swiped it at the register. But they don't bother to check the signature. What they do is key in the CVV code. The CVV is three digits printed on the back of the card, except for American Express, which prints four digits on the front of the card.

I honestly don't know of any POS system that asks for the CVV code. Typically, when any numbers are keyed in, it is the last four digits of the card, to prevent re-encoded credit card fraud. As for gas stations, if you show them it is a gift card (hence why they've switched to them), they will waive the zip code requirement, or not require it at all if you pay inside instead of at the pump.

Fraud, though, is a tiny number overall mostly because credit card companies tend to try to enforce investigations into the crime. Vs fraud in insurance claims which dwarfs credit card fraud by at least two orders of magnitude.

[cynwoody]

Typically, when any numbers are keyed in, it is the last four digits of the card, to prevent re-encoded credit card fraud.

That works, but CVV is better, because it catches even embossed counterfeits (although those are more difficult to make than simply recording an intercepted swipe).

http://www.amazon.com/Credit-Embossing-Plastic-Embosser-Machine/dp/B005F0B2G6
http://www.youtube.com/watch?v=FuP--kL1UcM

As for gas stations, if you show them it is a gift card (hence why they've switched to them), they will waive the zip code requirement, or not require it at all if you pay inside instead of at the pump.

That must be nerve-wracking for the thief, given a minimally well-designed POS would show the clerk what type of charge is being tendered (AX, DS, MC, VI, or gift card).