The S&P 500 rose 0.1% in midday trading to 2,531.97.
The Dow Jones Industrial Average increased 0.4% to 22,635.88.
The NASDAQ climbed 0.1% to 6,521.85.
The yield on a 10-year Treasury bond was down 0.2% to 2.33%.
The price of gold was flat at $1,276.
Irvine-based Endologix Inc. (NASDAQ: ELGX) jumped 16% to $5.62 and a $469 million market cap. The stock increased in seven straight trading sessions and is up 35% since Sept. 22, though still 58% below their 52-week high.
Anaheim-based Bridgford Foods Corp. (NASDAQ: BRID) increased 8.2% to $13 and a $118 million market cap on daily volume three times its 90-day average. Bridgford, which makes frozen and snack food products, is 28% below its 52-week high set in May.