US stocks drop ConAgra jumps on activist push

US shares fell modestly in early trade Friday, mostly shrugging off Shanghai's plunge, with ConAgra Foods surging on a push by activist investor Jana Partners to shake up the company.

About 30 minutes into trade, the Dow Jones Industrial Average was off 30.59 points (0.17 percent) at 18,085.25, and the broad-based S&P 500 slipped 3.88 (0.18 percent) to 2,117.36.

After sweeping to a new record Thursday, the Nasdaq Composite Index lost 10.72 points (0.21 percent) at 5,122.23.

The 6.4 percent plummet in Shanghai stocks and the Greek debt crisis "have not ruffled too many feathers here," said Patrick O'Hare of Briefing.com.

"The market is not trading in fear of a Greek debt default and eurozone exit."

ConAgra jumped 8.8 percent as hedge fund Jana reported amassing a 7.2 percent stake and moved for three board seats in an effort to change management direction and boost the company's value, complaining of poor performance in the wake of the 2103 $6.7 billion purchase of RalCorp.

Also in play was home lifestyle and furnishing group Martha Stewart Living Omnimedia, which added another 3.3 percent on top of Thursday's surge on news that retail fashion brands investor Sequential Brands Group was nearing agreement to buy the iconic firm.

Among other movers, Schlumberger was off 1.6 percent and McDonald's gained 0.6 percent.

Bond prices rose. The yield on the 10-year US Treasury slid to 2.28 percent from 2.34 percent Thursday, while the 30-year fell to 3.08 percent from 3.13 percent. Bond prices and yields move inversely.