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Tumblr founder David Karp was born and raised in New York City, attending the Bronx High School Science before dropping out at age 15. An internship at Frederator Studios led to a gig leading product at UrbanBaby. When CNET acquired the company in 2005, Karp started his own development agency, Davidville. In 2007 his team launched Tumblr, now the home and platform for more than 100 million creators. As a top 15 US network, Tumblr serves an audience of more than 170 million people worldwide.