Critics note that Romney's tenure as CEO of the leveraged buyout firm Bain Capital resulted in the loss of thousands of jobs through layoffs and bankruptcies.

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It began with a leveraged buyout firm in New York that I started with one of my investment banking clients, and then quickly moved to Hong Kong.

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More recently, the firm leveraged its market leadership in selling physical books online to become the dominant vendor of e-readers, leaving potential rivals such as Sony unable to gain much traction.

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