GOLDMAN Sachs says its second-quarter profit doubled, boosted by a surge in stock and bond underwriting.

Profit was US$1.9 billion after payments to preferred shareholders, compared with US$927 million a year ago.

Per share, those profits were US$3.70. Analysts polled by FactSet had expected US$2.83. Revenue was US$8.6 billion, up 30 percent from US$6.6 billion a year ago. That also beat the expectations of analysts, who had forecast US$8 billion.

In a statement, CEO Lloyd Blankfein called the quarter "solid," especially considering the "mixed economic sentiment."

The biggest increase in Goldman's earnings came from underwriting stocks and bonds, where revenue soared 45 percent.

The bank said it set aside more money for potential lawsuits and regulatory proceedings, but didn't give details. A former Goldman Sachs trader, Fabrice Tourre, went to trial on Monday in New York, accused of selling mortgage-backed securities that he knew would fail.