U.S. stocks dipped at the open on Thursday as worries over Greece's move to start official talks with its multilateral backers undercut a strong profit forecast from economic bellwether United Parcel Service Inc.

The Dow Jones industrial average <.DJI> dropped 14.44 points, or 0.13 percent, to 11,108.67. The Standard & Poor's 500 Index <.SPX> dipped 1.11 points, or 0.09 percent, to 1,209.54. The Nasdaq Composite Index <.IXIC> fell 0.12 point, flat percentage-wise, to 2,504.74.

(Editing by Jeffrey Benkoe)