The six-month ban imposed by the Federal Energy Regulatory Commission (FERC) is the latest sign that US authorities are stepping up their policing of the country's vast energy market. Last month, it proposed Barclays be fined $435m (£274m) for allegedly manipulating electricity prices. The punishment handed down to JP Morgan relates to a dispute that began in 2011, when the state operator of the power grid in California asked the bank for documents during an investigation into alleged price manipulation in the wider market. The California Independent System Operator (CAISO) fined the bank $486,000 in February for ... (full story)