Maurice R. Greenberg , the executive who built American International Group into a global insurance powerhouse and shaped an entire industry during nearly 40 years at the company 's helm , stepped down as chief executive yesterday after a series of run-ins with regulators raised questions about its complex and often obscure operations .
Maurice R. Greenberg /business/company_shareholder/major_shareholder_of American International Group
American International Group /business/company/major_shareholders Maurice R. Greenberg
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