Bloomberg News first reported on April 5 that Iksil had built an illiquid book of derivatives. The Federal Reserve and Office of the Comptroller of the Currency sought additional information about the trades following media reports.

The portfolio had a $415 million loss on April 10, the first trading day after news reports appeared. JPMorgan’s communications officer met with reporters to say that the activities were for hedging purposes and that regulators were fully aware of them, “neither of which was true,” according to the subcommittee’s report.

“Prior to the media reports in early April 2012, the synthetic credit portfolio had not been mentioned by name in any JPMorgan Chase public filing; over the next month, the SCP received sustained attention in the bank’s public filings, investor calls, and media communications,” the subcommittee wrote in the report.

‘No Hope’

Iksil’s book more than tripled from a net notional size of $51 billion in late 2011 to $157 billion by the time trading was shut down in late March of last year, the report says.

“There’s nothing that can be done, absolutely nothing that can be done,” Iksil said, according to a transcript of a March 16 call with a colleague. “There’s no hope.”

JPMorgan “dodged federal regulators and misled the public by hiding losses, by mismarking credit derivatives’ values,” Senator John McCain, the subcommittee’s ranking Republican, told reporters at a press briefing.

The OCC noticed that JPMorgan began withholding the chief investment office’s daily profit-and-loss report, which shows how much money the unit made or lost on a given trading day, in late January or early February of last year, according to the report. Dimon told executives to stop sending the data “because he believed it was too much information to provide to the OCC,” the report said, citing an interview with JPMorgan’s head OCC examiner Scott Waterhouse.

Risk Downplayed

The bank also said there was a data breach that prompted the company to limit the disclosures. When Dimon found out that then Chief Financial Officer Douglas Braunstein agreed to resume the reports, the CEO “reportedly raised his voice in anger” the report said.