U.S. stocks were slightly higher at the open on Monday, following three days of losses as investors remained cautious about Greece's fiscal future.

The Dow Jones industrial average <.DJI> was up 19.90 points, or 0.17 percent, at 11,954.48. The Standard & Poor's 500 Index <.SPX> was up 1.42 points, or 0.11 percent, at 1,269.87. The Nasdaq Composite Index <.IXIC> was up 2.33 points, or 0.09 percent, at 2,655.22.

(Reporting by Angela Moon)