Futures Remain Narrowly Mixed Despite GDP Report

U.S. stock index futures remained unchanged around the flatline Thursday despite a better-than-expected GDP report, as ongoing "fiscal cliff" uncertainties kept a lid on gains.

The economy grew at a faster-than-expected pace in the third quarter, expanding at a 3.1 percent annual rate, according to the Commerce Department, up from the 2.7 percent pace reported last month. Economists surveyed by Reuters had expected a reading of 2.8 percent.

Meanwhile, weekly jobless claims climbed 17,000 to a seasonally adjusted 361,000 in the previous week, according to the Labor Department. Economists polled by Reuters had expected a reading of 357,000. The four-week moving average for new claims, fell 13,750 to 367,750, the lowest since late October.

Boehner pressed his "Plan B" proposal that would extend the Bush-era tax cuts for those earnings up to $1 million, despite Obama's veto threat, saying it will be approved Thursday by the GOP-controlled House. (Read More: Fiscal Cliff Complete Coverage)

Meanwhile, Obama said the two sides were only $200 billion apart in a deal to avoid the looming "fiscal cliff," and he's ready to get the job done.

Merck slumped after the pharmaceutical company said its cholesterol drug study failed. The company said it no longer plans to seek approval for the drug in the U.S.

IntercontinentalExchange agreed to acquire NYSE Euronext in a deal worth nearly $8.2 billion. The offer values NYSE shares at $33.12, a 38 percent premium over Wednesday's closing price. Shares of both companies were halted. The acquisition is expected to close in the second half of 2013.

November existing home sales are due at 10:00 am, with Reuters expecting a gain of 1.3 percent, compared with 2.1 percent in October. And the Philadelphia Federal Reserve Bank's December business activity survey is forecast to come in at minus 3.0 compared to minus 10.7 in November.

Among earnings, Rite Aid surged after the drugstore chain posted its first quarterly profit in more than five years and boosted its forecast for the year.

ConAgra Foods edged higher after the packaged foods company posted better-than-expected earnings, and said its full-year profit will be at the high end of estimates.

Among earnings, Nike and Research In Motion are among notable companies slated to report after the closing bell.

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

Coming Up This Week:

THURSDAY: Existing home sales, Philadelphia Fed survey, FHFA home price index, leading indicators, Fed balance sheet/money supply, UPS busiest day; Earnings from Nike, Research In Motion, Micron
FRIDAY: Quadruple witching, personal income & outlays, Chicago Fed activity index, consumer sentiment, BLS state employment stats; Earnings from Walgreen

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