Brian Acton

American businessman and computer programmer

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July 22, 2026

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Brian Acton is an American businessman and computer programmer who co-founded the messaging application WhatsApp in 2009 with Jan Koum. Acton and Koum met while working at Yahoo!. After leaving Yahoo!, Koum created WhatsApp for the iPhone, and Acton joined him shortly after its launch, helping to secure initial funding. WhatsApp allows users to send text and voice messages, and engage in voice or video calls, supporting cross-platform and international communication. In 2014, Facebook acquired WhatsApp for $19 billion. Acton later left WhatsApp in 2017 to focus on user privacy with a new messaging service.12

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WhatsApp
…was founded in 2009 by Brian Acton and Jan Koum. Koum, a Ukrainian immigrant who had just begun attending classes at San Jose State University, and Acton, a Stanford-educated programmer, met while Acton was working for Internet pioneer Yahoo! in 1997. Koum was soon offered a job with the Mountain…
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…was founded in 2009 by Brian Acton and Jan Koum. Koum, a Ukrainian immigrant who had just begun attending classes at San Jose State University, and Acton, a Stanford-educated programmer, met while Acton was working for Internet pioneer Yahoo! in 1997. Koum was soon offered a job with the Mountain…
Read More