The S&P 500 rose 0.62% to 1,872.26 in afternoon trading Thursday.
The Dow Jones Industrial Average was up 0.70% to 16,335.71, while the Nasdaq was up 0.40% to 4,325.02.
The yield on a 10-year Treasury bond rose 0.18% to 2.78%.
The price of gold fell 0.79% to $1,330.70 per ounce.
Irvine-based disk drive maker Western Digital Corp. was up about 2.5% to $88.03 for a market value of $20.80 billion. An article on investor website Seeking Alpha maintained a bullish position on the company, citing a strong product pipeline.
Irvine-based Tilly's Inc. was off about 4% to $12.30 for a market value of $344.56 million. On Wednesday after market close, the company reported fourth-quarter results above Wall Street estimates, but guided below consensus net income estimates for the current quarter.