Jan Koum

Ukrainian-American businessman and computer programmer

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July 22, 2026

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Jan Koum is a Ukrainian-American businessman and computer programmer, best known as the co-founder of WhatsApp. He met Brian Acton, his future business partner, while working at Yahoo! in 1997. In 2009, Koum created WhatsApp for the Apple iPhone. Initially, the app was designed to show users' work statuses, but it quickly evolved into a popular messaging service. WhatsApp gained traction due to its ability to facilitate cross-platform and international communication. In 2014, Facebook acquired WhatsApp for $19 billion. Koum stepped down as CEO of WhatsApp in 2018.12

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…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 View, California-based company,…
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…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 View, California-based company,…
Read More