Bank executives, including Dimon, have argued for weaker rules and broader exemptions.
JPMorgan has been a strong critic of several provisions that would have made this loss less likely, said Michael Greenberger, former enforcement director of the Commodity Futures Trading Commission, which regulates many types of derivatives.
"These instruments are not regularly and efficiently priced, and a company can wake up one day, as AIG did in 2008, and find out they're in a terrific hole. It can just blow up overnight," said Greenberger, a professor at the University of Maryland.
The disclosure quickly led to intensified calls for a heavier-handed approach by regulators to monitoring banks' trading activity.
"The enormous loss JP Morgan announced today is just the latest evidence that what banks call 'hedges' are often risky bets that so-called 'too big to fail' banks have no business making," said Sen. Carl Levin, D-Mich.
AP Business Writer Pallavi Gogoi contributed to this report.
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