According to Seeking Alpha, the top five lenders could lose up to $1 billion in earnings as fears rise over trading revenue and higher legal costs.

JPMorgan has been particularly affected, with consensus for net income down $526 million to below $5 billion. The company's legal woes are seen adding $2 billion to expenses.

Analysts have lowered their net income for Bank of America by $128 million, for Goldman Sachs by $123 million, for Morgan Stanley by $97 million, and for Citigroup by $210 million. The latter has already reportedly told investors about a sharp drop in trading revenues.