Mittal overtook Arcelor as the world's largest steelmaker after buying America's International Steel Group in 2005.

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Ross made International Steel Group into one of the largest U.S. steel producers by acquiring embattled mills out of bankruptcy and whipping them into efficient money-making machines.

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Mittal, a private London-based company that gained control of America's International Steel Group earlier this year, is set to boost annual output to over 65m tonnes with the Ukrainian acquisition.

ECONOMIST: Steelmakers on a roll, until the next glut | The

Perhaps Ross' most famous move was orchestrating the ascension of his International Steel Group (nyse: ISG - news - people ), which became one of the largest U.S. steel producers by acquiring money-losing mills out of bankruptcy and making them more efficient.

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Ranina, a Mumbai-based corporate tax lawyer, said Mr. Mistry's key target would be to turn around Tata Group's international steel business and consolidate all the other businesses.

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