The S&P 500 rose 0.11% to 1,845.91 in afternoon trading Wednesday.
The Dow Jones Industrial Average was down 0.16% to 16,387.65, while the Nasdaq was up 0.45% to 4,244.90.
The yield on a 10-year Treasury bond rose 1.10% to 2.86%.
The price of gold was off 0.24% to $1,238.80 per ounce.
Irvine-based drug maker Allergan Inc. continued to recover from a 4% drop earlier today but is still down about 1% to $118.49. Actavis Inc., formerly Watson Pharmaceuticals Inc., filed for patent certification for a generic version of Allergan's dry eye drug Restasis. Allergan had a recent market value of $35.21 billion.
Software maker Quality Systems Inc., also in Irvine, was off about 3% to $18.20 after ISI Group downgraded the company's stock from "neutral" to "cautious." Quality had a recent market value of $1.09 billion.
Homebuilders were generally up on Wednesday. A Sterne Agee analyst assigned "buy" ratings on based on a positive outlook for the industry this year.
Irvine-based TRI Pointe Homes Inc. rose about 4% to $18.03 for a market value of $569.59 million.
Standard Pacific Corp. of Irvine was up about 3% to $8.69 for a market value of $3.02 billion.
Newport Beach-based patent licensor Acacia Research Corp. was up about 2% to $14.78 for a market value of $737.91 million. The company said its subsidiary Brandywine Communications Technologies LLC reached a patent license and settlement agreement with Toshiba Corp.