8. Kobi Alexander
Israeli-American businessman Kobi Alexander previously founded telecom tech firm Comverse Technology and served as its CEO. Comverse began as a big player in the voicemail services industry during the early days of cell phones, and Comverse eventually began generating serious money. However, Alexander’s luck ran out in 2006 when he and other executives were charged with involvement in a backdating scheme. He was subsequently sentenced to 30 months in prison for securities fraud.
