U.S. stocks rose at the open on Monday as a flurry of mergers offset data showing factory activity in New York State grew at a slower pace than expected.

The Dow Jones industrial average <.DJI> rose 14.36 points, or 0.14 percent, to 10,634.52. The Standard & Poor's 500 Index <.SPX> added 3.91 points, or 0.34 percent, to 1,139.59. The Nasdaq Composite Index <.IXIC> gained 9.45 points, or 0.40 percent, to 2,356.30.

(Editing by Jeffrey Benkoe)