Who is the London Whale?

The man at the center of JP Morgan Chase's $2-billion US loss is Bruno Iksil, a trader at its London-based Chief Investment Office.

Iksil, nicknamed "The London Whale" by The Wall Street Journal, is a French national who graduated in engineering from the prestigious Ecole Centrale University in Paris.

Iksil was brought into the CIO unit to head its credit desk, an asset class the unit had not previously covered, a person who worked in the unit told Reuters. It built up credit positions over several years through trades vetted by management and the losses now likely resulted from a combination of these trades, a person familiar with the matter said.

A month ago, The Journal said Iksil had amassed a huge position that prompted hedge funds to bet against him. On an earnings conference call last month, Dimon called the concern "a complete tempest in a teapot."

These traders say other banks have comparable functions to JPMorgan's CIO. The French banks, Citigroup, Deutsche Bank and UBS were all cited as examples of large treasury functions that hedge credit exposures in similar ways.

In a Securities and Exchange Commission filing, JPMorgan reported that since the end of March, its Chief Investment Office has had significant mark-to-market losses in its synthetic credit portfolio -- these typically include derivatives intended to mimic the performance of securities.

While other gains partially offset the trading loss, the bank estimates the business unit will post a loss of $800 million in the current quarter, excluding private equity results and litigation expenses. The bank previously forecast the unit would make a profit of about $200 million.