Stabilizing views on China and tech stocks led major indices higher in midday trading.
The S&P 500 was up 1% to 1,933.35. The Dow Jones Industrial Average was up 1.2% to 16,249.90. The Nasdaq was up 1.3% to 4,697.05.
The yield on a 10-year Treasury bond was up 0.2% to 2.18%.
The price of gold was down 0.5% to $1,134.
Huntington Beach-based Quiksilver Inc. was up 7% to 45 cents and a $77 million market cap. A news report said the surfwear maker has held discussions with potential bidders about a management-led buyout. Shares rose 30% in early trading before dropping back to midday levels on higher-than-average trading volume.