Bisnow had left the University of Wisconsin to cofound a newsletter company with his dad, Mark.

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He left Facebook last year to cofound private social-sharing site Path, which now has more than a million users.

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Edison would go on to found, cofound, or acquire more than 150 companies in more than a dozen industries, including General Electric.

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He also helped hire the two scientists instrumental in developing Amgen's blockbuster drugs, as well as Phil Whitcome, who went on to cofound Neurogen.

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He left to cofound Trafigura in 1993.

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