Inspired by early instant-messaging programs, Ma and a childhood friend launched their own service, QQ, in 1999. Once he had a captive audience, he added paid services like gaming and online dating.
Sales increased 78% in the first half of this year, to $788 million; Ma's stake is now worth $3.6 billion.
Nickname: "Pony" Ma (ma is the Chinese word for "horse").
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