Stock index futures briefly turned negative on Thursday after weekly data showed an unexpected rise in first-time claims for jobless benefits.

Futures were up earlier after China's benchmark stock index <.SSEC> gained 4.5 percent, easing some worries that a 20 percent fall in Chinese equities over the last two weeks meant equity prices were too far ahead of the economic recovery.

S&P 500 futures fell 0.4 points and were above 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 fell 6 points, and Nasdaq 100 futures shed 1.75 points.