Bernard Madoff ran the largest Ponzi scheme in history, defrauding thousands of investors of $65 billion. He founded Bernard L. Madoff Investment Securities in 1960 and grew it with help from friends and family who worked there. Despite claiming to use a split-strike conversion strategy, Madoff simply used new investments to pay earlier investors in a typical Ponzi scheme. The fraud collapsed in 2008 when many investors cashed out due to the financial crisis. Madoff pled guilty and was sentenced to 150 years in prison.