The S&P 500 rose 0.06% to 1,415 in midday trading Friday.

The Nasdaq was down 0.6% to 2,971, while the Dow Jones Industrial Average was up 0.39% to 13,125.

The yield on a 10-year treasury bond rose 2.78% to 1.62%.

The price of gold was up 0.03% to $1,701 per ounce.

Irvine-based DNA testing services company CombiMatrix Corp. surged 229% to $6.48 following studies published in the New England Journal of Medicine on testing for the diagnosis and evaluation of stillbirths. The studies favor a type of testing that is CombiMatrix's specialty. CombiMatrix had a recent market value of $7.5 million.

Newport Beach-based Acacia Research Corp. rose about 4% to $25 on news of a license and settlement agreement for one of the company’s subsidiaries. Acacia had a recent market value of $1.2 billion.