The Russian billionaire Oleg Deripaska’s ex-wife sold a 2.6 percent stake in the power and aluminum company En+ Group International to Abu Dhabi sovereign wealth fund Mubadala Investment Co. Mubadala is paying about $200 million for the stake in the company founded by Polina Yumasheva’s former husband, Bloomberg reported citing unidentified people familiar with the matter. The acquisition increases Mubadala’s stake in En+ to 2.86 percent on a fully diluted ...