Attorneys representing the estate of Lehman Brothers filed a lawsuit on Monday against Barclays Capital, in efforts to claw back as much as $10bn that it claims was transferred to the UK bank last year in the frenzied days following Lehman’s bankruptcy. The suit is the culmination of a one-year quest by Alvarez and Marsal, the consultancy hired by Lehman after its bankruptcy filing in September 2008, to determine whether billions of dollars worth of assets were improperly transferred to Barclays when it negotiated a deal to acquire the remains of Lehman.