Banks including JPMorgan Chase & Co. and Bank of America may pay more to resolve claims over their alleged roles in the collapse of a $2.3 trillion mortgage- backed securities market if sophisticated investors are allowed to sue as a group along with less savvy ones. Class-action status allows investors to pool financial and legal resources, giving them greater leverage to win larger settlements or verdicts. The banks, however, have a court ruling on their side that may help fend off such blockbuster cases. It says class status is barred because some investors are too sophisticated — in fact, because some of them are other banks, including JPMorgan.