Stock futures are mixed with U.S. companies posting varying quarterly results.

Dow Jones industrial futures are down 18 points to 13,558. The broader S&P futures have added 1.6 points to 1,477.30. Nasdaq futures are up a point to 2,734.75.

Verizon posted a wider loss for the fourth quarter Tuesday, and DuPont said weakness in electronics and communications and chemical sales. DuPont's profit dropped 70 percent, though it still beat Wall Street expectations.

So did Delta Airlines, even after taking a $75 million hit to revenue from Superstorm Sandy.

Johnson & Johnson beat most expectations for the final quarter of the year, but shares slipped before the opening bell due to a weak forecast for this year.

Earnings reports continue after the market closes with Google, IBM, CSX and Norfolk Southern.