A trader on the New York Stock Exchange enters a Chase bank branch in New York City. - 

Jeremy Hobson: The losses at JPMorgan are being attributed to a London trader named Bruno Iskill, also known as the London Whale.

Marketplace's Stephen Beard reports.

Stephen Beard: The trader acquired his nickname as a result of his huge appetite for complex securities and his dominant role in the market. One flick of his tail -- it was said -- one spurt from his blowhole would send ripples around the globe. Well the Whale has now reportedly swamped JPMorgan with losses. His bets apparently went horribly wrong.

But bank analyst Ralph Silva says it's not fair to pin everything on the Whale -- a lot of smaller fry may also be to blame.

Ralph Silva: To say that it was specifically one trading desk is inappropriate because the positions actually move throughout the time zones. So when the markets close in the U.S. they move to Asia. And it literally goes around the world. So everyone was responsible.

Anyway, the losses will reverberate throughout the banking industry and make it harder to argue that tough new regulations should be watered down.

I'm Stephen Beard for Marketplace.