The Dow Jones industrial average fell 30 points to 13,442 after the first half-hour of trading. The S&P 500 fell three points to 1,468 and the Nasdaq composite index dropped three points to 3,119.
Wells Fargo, the first major bank to report earnings, dropped even after the bank reported a 25 percent increase in fourth-quarter earnings, as analysts questioned the sustainability of the banks' profits. The bank's stock fell 65 cents to $34.75.
Boeing fell $1.54 to $75.57 after the U.S. Federal Aviation Administration said it is launching a comprehensive review of the critical systems of Boeing's 787, the aircraft maker's newest and most technologically advanced plane, after a fire and a fuel leak earlier this week.
The S&P 500 closed at a five-year high Thursday after the stock market got a boost from reports suggesting the outlook for economic growth may be improving. European Central Bank President Mario Draghi said the struggling euro zone should start growing again later this year and a report showed that China, the world's second-biggest economy, may gradually be emerging from its worst economic downturn since the 2008 global crisis.
Stocks are up on the year after a lawmakers came up with a last-minute deal to avoid the U.S. going over the "fiscal cliff," averting the threat of a series of tax hikes and spending cuts that economists say would almost certainly have pushed the U.S. economy into recession.
The yield on the 10-year Treasury note, which moves in an opposite to the security's price, rose 1 basis point to 1.91 percent.
Other stocks making big moves;
— American Express rose 91 cents to $61.72 after the company said that spending by cardholders jumped 8 percent in the fourth quarter, even after Superstorm Sandy crimped some buying.
— Best Buy jumped $1.59 to $13.81 after the struggling consumer electronics chain reported holiday sales. The company's U.S. performance was flat and, while this was a hair below the 0.3 percent increase Best Buy reported in the prior-year period, it was an improvement over the past several quarters.