Overview

• A trader's input mistake led to $1.4 billion in erroneous stock orders on European exchanges.
• The flash crash briefly erased $322 billion in market value before recovery.
• Citigroup's internal controls failed to block all parts of the erroneous order.
• The bank has since taken steps to improve its trading systems and controls.
• Total financial impact on Citigroup from the incident is around $130 million, including fines and losses.