Stocks opened slightly lower on Wednesday, putting the S&P 500's three-day winning streak in jeopardy after weaker-than-expected euro zone economic data.

The Dow Jones industrial average <.DJI> was down 12.11 points, or 0.09 percent, at 12,953.58. The Standard & Poor's 500 Index <.SPX> dipped 1.86 points, or 0.14 percent, at 1,360.35. The Nasdaq Composite Index <.IXIC> was off 7.15 points, or 0.24 percent, at 2,941.42.

European shares fell for a second straight session as recession concerns increased after data showed the euro zone's service sector unexpectedly shrank and amid residual worries about Greece despite its success in getting a bailout.

(Reporting By Ryan Vlastelica; editing by Jeffrey Benkoe)