JON PLATT, 51
Last Year's Rank: 46
As Warner/Chappell rises, so does Platt. Promoted to CEO in November, he'll add chairman duties in May. ln third-quarter 2015, the publisher captured 19.4 percent of the top 100 radio songs — its highest since Billboard began tracking that market-share measure — due in part to songwriters Julia Michaels and Justin Tranter (Justin Bieber's "Sorry," Selena Gomez's "Good for You") and Twenty One Pilots. Capping the year: multiple Grammy nods for Kendrick Lamar and Chris Stapleton.