Traders work on the floor of the New York Stock Exchange
Traders work on the floor of the New York Stock Exchange September 28, 2011. REUTERS

Stock index futures fell on Thursday after weaker-than-expected economic data in China reawakened global economic worry and earnings from JPMorgan Chase.

China's trade surplus narrowed for a second straight month in September, as both imports and exports were lower than expected, reflecting global economic weakness and domestic cooling.

Shares of JPMorgan Chase Co , the first of the U.S. big banks to release third-quarter results, were off 0.7 percent to $32.96 in premarket after posting third-quarter earnings.

The S&P 500 is up about 12 percent from its intraday low hit last week on Tuesday and had its largest seven-day rally since March 2009.

S&P 500 futures fell 3.8 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures shed 22 points, and Nasdaq 100 futures lost 5.25 points.

Economic data on tap includes weekly U.S. jobless claims, due at 8:30 a.m. (1230 GMT), with economists in a Reuters survey forecasting 405,000 new filings compared with 401,000 in the prior week.

Also at 8:30 a.m (1230 GMT), the Commerce Department releases data on August international trade. Economists in a Reuters survey forecast a $45.8 billion deficit compared with a $44.81 billion deficit in July.

Google is reporting third-quarter earnings after the close and investors will be looking to see how the slowing economy is impacting its advertising business.

A report on Wednesday that Akamai Technologies Inc was close to being acquired by Google has no merit, a person familiar with the matter said. Akami shares were up 4 percent to $24.30 in premarket trade.

The CEO of AOL Tim Armstrong has been pushing the idea of a sale to Yahoo to top shareholders, which could see the company save $1.5 billion, according to sources with knowledge of the discussions.

Pratt & Whitney, a unit of United Technologies Corp has agreed to buy Rolls-Royce Holding's share of the International Aero Engines consortium in a $1.5 billion deal.

Bloomberg reported, citing people with knowledge of the matter, that DuPont Co is seeking buyers for its polyester-film joint venture as well as its powder-based paint business.

European shares slipped in choppy trading in the morning, after recent strong gains, with mining stocks among the biggest casualties after Chinese trade data was weaker than expected. <.EU>

* Asian shares rose on growing optimism that Europe will take concrete steps to contain the region's debt woes and head off a systemic banking crisis

* U.S. stocks rose on Wednesday as Europe's progress toward bolstering its financial rescue fund brought more battle-weary investors back into the market.

(Reporting by Chuck Mikolajczak; Editing by Chizu Nomiyama)