TV Article Yahoo plans to buy Tumblr for $1.1 billion By Kerrie Mitchell Published on May 19, 2013 12:00PM EDT Yahoo agreed to buy the blogging service Tumblr for around $1.1 billion in cash, reports The New York Times. If the deal is approved, it would be the biggest yet under the tenure of new Yahoo CEO Marissa Mayer and a major move into social media for the Internet company. (It would also top Facebook’s acquisition of Instagram for $1 billion last year.) Founded in 2007, Tumblr has a young, active user base, with over 108 million blogs, that Yahoo will likely want to tap into.