Billionaire entertainment mogul David Geffen has split up with his long-term partner, Jeremy Lingvall. Sources tell us the pair have gone their separate ways after six years together, because “the relationship had simply run its course.” The source added, “There is nobody else involved.” Geffen, 68, confirmed the split last night but refused to comment further. He and Lingvall had long been inseparable despite a 40-year age difference between them. Indisputably handsome actor Lingvall, a graduate of the University of California, was often seen aboard Geffen’s yacht and accompanying him to high-profile events, including President Obama’s first state dinner at the White House.