“Banks are urging U.S. authorities to broaden a little-noticed exemption in the Volcker rule’s trading curb that critics say could blind regulators to the next version of the JPMorgan Chase & Co Whale trade.

The forthcoming Volcker rule to curb proprietary trading is one of the most hotly debated measures called for in the 2010 Dodd-Frank financial reform law.”….

Mark Jarsulic, chief economist at Better Markets, a reform advocacy group, isn’t buying the banks’ argument and said the proposal already gives banks too much authority to dictate what trades provide liquidity.

Read Alex Alper’s full story here