The S&P 500 was down 0.2% in midday trading to 2,097.42.

The Dow Jones Industrial Average was up 0.2% to 17,916.69.

The Nasdaq was down 0.9% to 5,067.08.

The yield on a 10-year Treasury bond was up 3.7% to 2.48%.

The price of gold was up 0.2% to $1,174.

HEALTHCARE

Laguna Hills-based Glaukos Corp. was down 8% to $28.75 and an $870 million market cap on profit-taking after Thursday’s initial public offering. The glaucoma-surgery device maker yesterday priced its offering of 6 million shares at $18, opened at $29 and closed above $31, for a first-day jump of 73% compared with its offering price.

TECHNOLOGY

Irvine-based Western Digital Corp. was down 2% to $84 and a $19.4 billion market cap. Boise-based Micron Technology Inc., which makes chips for storage devices, reported a 40% year-over-year drop in quarterly earnings and provided weak guidance for its current quarter.