Stocks are little changed in early trading as traders keep a close eye on developments in Iraq.
Deal news lifted a handful of stocks. Covidien soared 27 percent after the Ireland-based medical device manufacturer agreed to be bought by U.S. competitor Medtronic.
Williams Companies rose 20 percent after announcing a deal to expand its stake in Access Midstream Partners.
The Dow Jones industrial average lost 10 points, less than 0.1 percent, to 16,764 points in the first few minutes of trading Monday.
The Standard & Poor's 500 index edged up two points, or 0.1 percent, to 1,938. The Nasdaq composite rose seven points, or 0.2 percent, to 4,317.
Bond prices were flat. The yield on the 10-year Treasury note held steady at 2.60 percent.