US banks mull legal action against fed regulators in major move.

TLDR: Major US banks, including JPMorgan Chase, Citibank, and Goldman Sachs, are considering taking legal action against federal regulators over proposed rules that would increase capital reserve requirements. The changes are part of the Basel III agreement and would require large banks to increase their capital reserves by an average of 16 percent. The banks argue that the proposed rules would have a greater impact on capital reserves than the stated average and could harm the US economy. They also allege that the rule changes would violate the Administrative Procedure Act.