AmTrust Financial Owners

New York, New York

Until Michael’s death last year, George and Michael Karfunkel owned a majority of the publicly traded insurance firm AmTrust Financial. Their family fortune includes stakes in a variety of other insurance companies. The brothers bolstered their wealth considerably when they sold a stock transfer agency they owned for $900M in 2008.

AmTrust is led by Michael’s son-in-law, Barry Zyskind. In 2011, the firm’s real estate arm bought a 23-story Cleveland office building, the KeyBank Center, as its vacancy was about to hit 60%. It also owns office buildings in Lower Manhattan and downtown Chicago. — Scott Klocksin