Deutsche Bank AG faces a claim that may be worth billions of dollars in a lawsuit with investment fund Sebastian Holdings Inc. over failed foreign exchange transactions. Sebastian said in court papers filed in London that Germany’s largest bank allowed a trader to breach currency- trading limits between 2006 and 2008. Sebastian, owned and run by Norwegian investor Alexander Vik, said it suffered losses and missed out on profits worth about $2.5 billion when it had to meet margin calls and close out positions because of the dispute. “This is about a margin call that was missed and remains unpaid,” Deutsche Bank said ... (full story)