in july 2012, tnk-bp was sold to the state-owned rosneft for $56 billion, a process which was still underway by early 2013. reuters described it as "one of the biggest energy takeovers in history," with the overall deal worth $55 billion. khan officially left tnk-bp in march 2013 after alfa group sold its 50% stake in tnk-bp to rosneft for $28 billion. khan earned around $3.3 billion in the deal. using the $14 billion raised from selling their stakes in tnk-bp, khan joined mickhail fridman in establishing letterone (l1), based in luxembourg, for the purpose of investing the proceeds from the sale of tnk-bp in international projects.