The S&P 500 rose 0.39% to 1,687.50 in afternoon trading Thursday.
The Dow Jones industrial average was up 0.45% to 15,540.15, while the Nasdaq was down 0.06% to 3,607.95.
The yield on a 10-year Treasury bond rose 1.36% to 2.52%.
The price of gold was up 0.46% to $1,283.40 per ounce.
Irvine-based healthcare software maker Quality Systems Inc. rose about 4% to $22.80, a day after the company said it planned to add three nominees from New York-based Clinton Group Inc. to its board of director. Quality had a recent market value of $1.36 billion. JPMorgan upgraded the company's stock from "underweight" to "neutral."
Irvine-based disk drive maker Western Digital Corp. was up about 2% to $69.66 for a market value of $16.47 billion. Rival Seagate Technology PLC was also up less than 1% to a market value of $16.82 billion.