Acton spent eight years with WhatsApp, which Facebook bought in 2014 for $19 billion in cash and stock.
Acton announced the departure to colleagues at a WhatsApp all-hands meeting at Facebook headquarters on Tuesday, and posted the news to his Facebook page later that afternoon.
Mr. Acton's exit comes as WhatsApp lays the groundwork to make.
WhatsApp was co-founded by Brian Acton and Jan Koum in February 2009.
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"It's something I've thought about for a while, and now it's time to just focus and execute", the 45-year-old added. Though, he did not share more concrete details about his new venture. According to Forbes, Acton has a net worth of $6.5 million. This decision is, of course, a tough one.
It is no small development for messaging app giant WhatsApp.
After working at Yahoo, Acton was ironically rejected by Facebook in 2009 when he went for an interview. In the post, Brian Acton revealed why he took such a decision of leaving his brain child. I'm proud of what our team has accomplished in only a few years, and it's humbling to see that so many people rely on WhatsApp every day. "WhatsApp for Business" as it is being called recently saw a soft launch in India and BookMyShow is one of the company's known partners and early adopters.
Further, the leaks suggest that the when the sender deletes the message for everyone, WhatsApp will delete it in the Notification Center.