The S&P 500 was up down 0.5% in midday trading to 2,069.79.
The Dow Jones Industrial Average was down 0.7% to 17,444.63.
The Nasdaq was down 0.9% to 5,044.92.
The yield on a 10-year Treasury bond was down 2% to 2.22%.
The price of gold was up 1% to $1,095.
Irvine-based CoreLogic Inc. was down 2.7% to $39.31 and a $3.5 billion market cap in a second day of declines after posting its quarterly results Friday, when shares fell about 5%.
Santa Ana-based QuantumSphere Inc. was up 9% to $2.85 and a $63 million market cap on higher volume. The ammonia products maker went public last July by merging with a Nevada shell company and said last week it has completed a manufacturing facility here.
Irvine-based CombiMatrix Corp. was down 11% to $1.40 and an $18 million market cap. The DNA-testing services company had by midday traded about double the shares of its 90-day average.