US stocks : Dow flat, S&P up 0.1 pct

Still, some recent comments from politicians suggest a compromise might be more likely this time, Gendreau said.

NYSE first alerted traders it was having problems with one of its cash equity matching engines at 9:38 a.m. and said it would not publish quotes on a total of 216 stocks, including CVS Caremark Corp and Lazard Ltd.

Nasdaq OMX Group, BATS Global Markets, and Direct Edge exchanges stopped sending orders to the NYSE, and investors wishing to trade in those shares did so on these exchanges rather than the NYSE. The NYSE said trading in those issues would return to normal on Tuesday.

The S&P index hovered around its 200-day moving average after last week closing below the level for the first time in five months. An extended run under it could signal further losses ahead.

The Dow Jones industrial average slipped 0.23 point to 12,815.16. The Standard & Poor's 500 Index added 0.15 point, or 0.01 percent, to 1,380.00. The Nasdaq Composite Index was off 0.62 point, or 0.02 percent, to 2,904.25.

The S&P 500 is still up about 10 percent for 2012, though recent months have eroded those gains. The Nasdaq has fallen for five straight weeks.

Volume was roughly 4.62 billion shares on the New York Stock Exchange, the Nasdaq and the NYSE MKT, well below the year-to-date average daily closing volume of 6.52 billion.

Decliners outnumbered advancers on the NYSE 1,539 to 1,406 on the New York Stock Exchange. On the Nasdaq, decliners outpaced advancers by 1,304 to 1,121.

Merger

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