Serge Humpich is a person who discovered a serious flaw in the Carte Bleue system used in France for credit cards. He tried to contact banks without success for warning them, and so decided to perform a public "show" where he bought subway tickets while using the flaw in the card system. He was convicted in 2000 to a ten months suspended sentence. He was 36 at the time, and lost his job as a result of the case.
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