Which CEO has the most influence when it comes to social media? Warren Buffett? Nope. Michael Dell? Not a bad guess, I suppose. AOL’s Steve Case? Good try. Richard Branson? You’re getting warmer.

According to the Reuters & Klout 50, which measures the most influential executives online, Oprah Winfrey  is the most influential social CEO, ahead of Rupert Murdoch, Richard Branson, Mark Cuban and Tim O’Reilly. Twitter co-founder (and now Square CEO) Jack Dorsey placed in fifth, while Twitter CEO Dick Costolo was fourteenth.

Also see: Top 30 Richest Internet Entrepreneurs in the World [2013]

What about Facebook’s Mark Zuckerberg? No, he doesn’t even make the top fifty.

Check out the below infographic below for top 40 Most Influential CEOs on Social Networks.