He became a billionaire by venturing into the production of these items in the early 2000s.

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Pierre Omidyar was 31 years old when he became a billionaire in one afternoon.

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The donation is the second biggest announced by the hedge fund tycoon publicly since he became a billionaire.

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The Tufts grad was 31 years old when he became a billionaire in one afternoon with eBay's 1998 IPO.

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He later became a billionaire by buying credit default swaps on subprime mortgage-backed bonds as housing crashed.

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Instead, he co-founded PayPal and became a billionaire.

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