S&P Snaps 6-Day Win Streak; Apple Falls

Stocks ended in negative territory Thursday, with the S&P 500 snapping a six-day win streak, as ongoing jitters over the "fiscal cliff" negotiations kept investors nervous.

Stocks eased off their worst levels in the final minutes of trading following news that House Speaker John Boehner will meet President Barack Obama at the White House, with investors hoping for some developments on the "fiscal cliff."

S&P 500

The Dow Jones Industrial Average fell 74.73 points, or 0.56 percent, to close at 13,170.72, led by Merck and UnitedHealth.

The S&P 500 declined 9.03 points, or 0.63 percent, to end at 1,419.45. The Nasdaq erased 21.65 points, or 0.72 percent, to finish at 2,992.16. The CBOE Volatility Index (VIX), widely considered the best gauge of fear in the market, ended above 16.

All key S&P sectors finished in the red, led by energy and health care.

"The market is betting the U.S. will not roll over the fiscal cliff—that does not mean an agreement will be reached by the end of the year, however," wrote Scott Wren, senior equity strategist at Wells Fargo Advisors. "The negotiating process could easily continue into mid-to-late January before a final agreement is signed, sealed and delivered. Some of the Santa Claus rally is likely already priced into stocks."

Earlier, Boehner reiterated that "serious differences" remain between him and Obama, saying the president hadn't made a proposal to cut spending. Stocks have zig-zagged in recent weeks on headlines from Washington.

"The President still has not made an offer that meets the standards, but Republicans have," said Boehner in a press conference. "It's clear that the President is just not serious about cutting spending, but spending is the problem."

Adding to woes, ratings agency S&P revised its outlook on UK to "negative" from "stable," adding there is a "one-in-three chance" that the ratings could be lowered if the UK's economic and fiscal performances weaken beyond current expectations.

Earlier, top central banks around the world including the Federal Reserve, the ECB, the Bank of England agreed to extend their arrangements to extend their credit lines for another year. The Bank of Japan is to consider the measure at its next meeting.

"It's another sign that they're going to be incredibly accommodative," said Joe Bell, senior equities analyst with Schaeffer's Investment Research. "There's been a lot of market uncertainty and this is the Fed's way of trying to give some certainty to the market."

On Wednesday, the Federal Reserve met market expectations with another round of easing, this time with a pledge to keep interest rates low until unemployment falls below 6.5 percent and inflation tops 2.5 percent. But Chairman Ben Bernanke pointed out that even after the employment and inflation targets are triggered, that won't lead to an automatic raising of rates.

He also reiterated fear over the "fiscal cliff," saying that even the Fed's massive balance sheet expansion wouldn't be enough to stave off the effects, though the Fed may accelerate its asset purchases should cliff take effect. (Read more: El-Erian: Why Markets Shrugged Fed's Historic Move)

Apple declined nearly 2 percent following news that Google's mobile navigation application Google Maps will be available in Apple's app store. In September, Apple dropped Google's mapping service to launch its own when the tech giant launched the iPhone 5 and rolled out its iOS 6 mobile software platform.

Facebook rallied a day ahead of the social-networking giant's last big stock lock-up expiration, where nearly 156 million shares are expected to be released. The company's shares have surged more than 30 percent in the last three months, but still far from its market debut price of $38 a share.

Best Buy surged to lead the S&P 500 gainers amid expectations founder Richard Schulze will make a formal takeover offer for the consumer-electronics retailer this week in the range of $5 billion to $6 billion, according to a report.

Solarcity soared nearly 50 percent in its market debut on the Nasdaq under the ticker symbol "SCTY." The IPO was priced at $8 a share, which was much lower than the expected range.

Sprint Nextel is offering $2.90 a share to buy the rest of wireless Internet provider Clearwire that it doesn't already own. Clearwire shares soared nearly 15 percent.

CVS Caremark rallied to hit an all-time high after the pharmacy chain said it expects 2013 earnings to grow above this year's expected level and declared a 38 percent dividend increase.

Yum Brands gained after Goldman Sachs upgraded the parent company of KFC and Pizza Hut to "buy" from "neutral."

Among earnings, Adobe Systems is expected to post results after the closing bell.

Meanwhile, the Nasdaq announced that it will cancel a batch of erroneous pre-market trades that were greater than 10 percent away from the prior day's consolidated closing price. Stocks that were affected includes Citigroup, Hewlett-Packard, AT&T, Goldman Sachs, Wells Fargo and Kroger.

On the economic front, producer prices declined for the second month in November, according to the Labor Department, as the cost of energy dropped the most in over three years.

Jobless claims fell for the fourth-straight week, dropping 29,000 to a seasonally adjusted 343,000, according to the Labor Department. Meanwhile, the four-week moving average for new claims fell 27,000 to 381,500. And retail sales edged up in November, according to the Commerce Department, but the gain was less than expected. Meanwhile, business inventories gained in October, in line with expectations.

Treasurys declined after the auctioned $13 billion in 30-year bonds at a high yield of 2.917 percent. The bid-to-cover was 2.50.

—By CNBC's JeeYeon Park (Follow JeeYeon on Twitter: @JeeYeonParkCNBC)

Coming Up This Week:

FRIDAY: CPI, industrial production, Facebook lockup lifts

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