American businessman, investor and former credit analyst Ira Rennert has an estimated net worth of $5.95 billion as of March 2017, according to Bloomberg. He made his first fortune in junk bonds in the 1980s. Using junk bonds to finance his acquisitions of companies, often in bankruptcy, he has amassed significant holdings in basic, cyclical industries including mining and metals such as lead smelters, coal mines, magnesium producers and vehicle assembly lines. He currently controls one of the nation’s largest privately held industrial empires and is now considered as one of the richest people in New York. His personal home in Sagaponack, New York is also one of the largest in the US with 29 bedrooms and 39 bathrooms.

Born Ira Leon Rennert in Brooklyn, New York, he graduated from Brooklyn College and earned his master’s degree from New York University’s Stern School of Business where he is currently on the Board of Overseers. In 1956, he started his career as a credit analyst on Wall Street. He then attempted to launch his own securities firm in the early 60s but he was found to be in violation of the net capital rule that led to his ban from working in securities. After several failed business attempts, he began working for a junk bonds company, Integrated Resources, Inc. In the late 1980s, he launched his own company, Renco Group, after working for Integrated Resources. The holdings include US Magnesium and the Doe Run Company, a mining outfit in Peru that is the subject of a long-running pollution suit. He has since grown his business into one of the largest in the United States.

In 1992, Ira Rennert paid $133 million for military contractor AM General, which started selling consumer Hummers. He sold a majority stake in 2004 to billionaire Ronald Perelman’s MacAndrews & Forbes for $930 million. He bought steel assets in 2011 from Russia’s OAO Severstal through a new company, RG Steel. After 14 months, RG field for bankruptcy and laid off 4,000 workers while giving company executives $20 million in bonuses. Its creditors sued, accusing Rennert of delaying bankruptcy proceedings for personal gain in January 2013. However, the creditors withdrew the suit a month after. He is a supporter of Jewish causes. He has given $2 million to the Albert Einstein College of Medicine and $1 million to the pro-Romney Restore Our Future political action committee.