Why JPMorgan Chase earnings came out early

Adam Jeffery | CNBC

JPMorgan Chase surprised Wall Street when the bank's third-quarter earnings report appeared very early on Tuesday, several hours sooner than expected.

"At approximately 3.36 AM EST, inadvertently made a supplemental earnings file from JP Morgan Chase's third-quarter earnings announcement publicly accessible," Nasdaq said in a statement. "The root cause was a human error internally at The issue was contained only to JPMorgan Chase and did not impact any other clients."

Big banks out with results
Big banks out with results

In 2006, Nasdaq acquired, which specializes in shareholder communication and investor relations intelligence services.

JPMorgan later confirmed the leaked document, with the biggest U.S. bank posting earnings of $1.36 a share on revenue of $25.1 billion.

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Citigroup and Wells Fargo also reported quarterly results before the bell on Tuesday.