Stocks fell at the open on Friday after reports that Standard & Poor's was set to downgrade the ratings on several euro zone countries.

The Dow Jones industrial average <.DJI> was down 86.05 points, or 0.69 percent, at 12,384.97. The Standard & Poor's 500 Index <.SPX> took off 10.42 points, or 0.80 percent, at 1,285.08. The Nasdaq Composite Index <.IXIC> dropped 20.99 points, or 0.77 percent, at 2,703.71.

A senior euro zone source said S&P would announce the downgrades of several nations later Friday, adding that Germany was not one of them.

(Reporting By Angela Moon; editing by Jeffrey Benkoe)