U.S. stocks opened lower on Monday as renewed concerns about the euro zone sovereign debt crisis overshadowed the lift from several large acquisitions.

* The Dow Jones industrial average <.DJI> fell 27.55 points, or 0.24 percent, at 11,647.21. The Standard & Poor's 500 Index <.SPX> lost 3.07 points, or 0.24 percent, at 1,268.43. The Nasdaq Composite Index <.IXIC> dropped 11.77 points, or 0.44 percent, at 2,691.40.

(Reporting by Chuck Mikolajczak)

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