U.S. stocks closed mixed on Wednesday, coming off morning highs amid economic reports and central bank news.
"I think all eyes will be on the ECB, especially on the heels of the Jackson Hole meeting," Todd Salamone, senior vice president at Schaeffer's Investment Research, said.
The European Central Bank is scheduled to hold its monthly policy meeting on Thursday and may announce the launch of a bond-buying program.
"Obviously that's going to be very, very important," Scott Brown, chief economist at Raymond James, said. "Markets have priced in some quantitative easing from the ECB, so they may be disappointed."
Apple had its worst day in more than 7 months as shares lost more than 4 percent, earlier sending the Nasdaq lower almost 0.70 percent and the S&P 500 down 0.13 percent.
"I think that Apple is just being used as an excuse for the market going down," Marc Chaikin of Chaikin Analytics said. "I don't think the news out of Samsung is really that significant."
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Samsung revealed two large-screen phones and a virtual reality device on Wednesday at simultaneous events in New York, Beijing and Berlin, ahead of Apple's expected unveiling of the iPhone 6 next week.
With market composite volume slightly below average, Salamone also noted a hesitancy to buy and a tendency to sell in the markets on Wednesday.
"I think a lot of people are looking at their gains this year and taking a little off the table," Kim Forrest, senior equity analyst at Fort Pitt Capital, said. "Even though the Ukraine situation seems to be coming off the boil, investors don't seem to be happy about the data we got today."
On Wednesday, stocks held to earlier trends after July factory orders rose in-line with expectations, strong U.S. auto sales for August, and the release of the Fed's Beige Book, which found modest to moderate economic expansion.
"It takes a long time to disseminate [that news]," Art Hogan, chief market strategist at Wunderlich Securities said. "I would say that [the ECB] is the next signpost up ahead. We'll be on the edge of our seats for any acknowledgement of a purchase plan."
Earlier, stocks had opened positive on the possibility of a cease-fire between Ukraine and Russia.
"The conflict between Russia and Ukraine is more for traders, but not for long-term investors," Nick Raich, CEO of The Earnings Scout, said. In terms of economic data, "the rest of the world is slowing and the U.S. is doing pretty well."
Although the data did not move markets much, analysts saw a generally positive trend in the economy.
"We were off a good earnings season [and] good auto sales," JJ Kinahan, chief strategist at TD Ameritrade, said. "There are a lot of really good indicators outside of the economic indicators."
Thursday will bring a slew of data, including weekly jobless claims and ISM non-manufacturing data, ahead of Friday's job's report.
"It would appear that [the situation] would be moving in the right direction," Jack Ablin, chief investment officer at BMO Private Bank, said.
However, the press office later toned down the statement after Russia denied the deal.
Pro-Russian separatists have been battling Kiev's forces in the mainly Russian-speaking Donbass region, which is home to most of Ukraine's heavy industry and accounts for about 18 percent of the country's economic output.
In the minutes following the open, the S&P 500 and Dow traded at record highs.The Nasdaq and Nasdaq 100 were also at 14-year highs before turning negative.
The closed just above a benchmark at 2,000.72, down 1.56 points, or 0.08 percent, with utilities leading the six advancing sectors and information technology the hardest hit owing to Apple's decline.
The Nasdaq closed down 25.6 points, or 0.56 percent, at 4,572.57.
The CBOE Volatility Index (VIX), widely considered the best gauge of fear in the market, traded near 12.
For every eight decliners, seven advanced on the New York Stock Exchange, with an exchange volume of 614 million and a composite volume of 2.8 billion.
The benchmark 10-year Treasury note yield fell to 2.40 percent from 2.44 percent in the morning. The U.S. dollar declined slightly against major world currencies.
Crude oil futures closed up $2.66 on the New York Mercantile Exchange at $95.54 a barrel. Gold futures rose $5.30, or about 0.40 percent, to settle at $1,270.30 an ounce.
Nokia said it is releasing new free mapping apps for consumers, trying to compete with similar services from Google and Apple. Nokia said they would be released before the end of the year, and that unlike competitive products, they will work without an internet connection.
JPMorgan Chase was upgraded to "buy" from "neutral" at Nomura Securities, which downgraded Bank of America to "neutral" from "buy" at the same time. The ratings changes were based largely on each bank's ability to deal with new capital requirements.
Toll Brothers, the largest U.S. luxury homebuilder, said its quarterly income more than doubled. Also reporting before the bell, Vince Holding said its sales increased nearly 17 percent and saw continued momentum in e-commerce.
On tap this week:
8:15 a.m.: ADP employment for August
8:30 a.m.: Weekly jobless claims
8:30 a.m.: Trade deficit for July
8:30 a.m.: Productivity for the second quarter
10 a.m.: ISM non-manufacturing for August
8:30 a.m.: Nonfarm payrolls for August
8:30 a.m.: Unemployment rate for August
—By CNBC's Evelyn Cheng.
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