On Dec. 11, 2008, news broke that Wall Street legend and former chairman of Nasdaq, Bernard Madoff, had been arrested for running a Ponzi scheme that was believed to be a $50 billion fraud. Almost immediately, federal prosecutors launched a criminal investigation into Madoff, his co-workers, and the operations of Bernard L. Madoff Investment Securities, LLC. Yesterday, Irwin Lipkin, a 77-year-old man who was the Madoff firm’s controller for over 30 years, was sentenced to six months in prison. Lipkin is the 15th — and final — defendant to be prosecuted in the Madoff case, which prosecutors have now reportedly wrapped up.