US STOCKS-Nasdaq slumps to worst day since July; S&P 500 dips
* Nasdaq has worst day since July
* Tech sector stumbles as investors prepare for Alibaba
* Indexes: Dow up 0.26 pct, S&P off 0.07 pct, Nasdaq off 1.07 pct
By Chuck Mikolajczak
NEW YORK, Sept 15 (Reuters) - U.S. stocks closed mixed on Monday as the tech sector dragged the Nasdaq to its worst day since July and kept the S&P 500 near the unchanged mark as investors cleared the decks for Alibaba's debut planned for later this week.
Alibaba's could be the largest initial public offering in history and has seen "overwhelming" interest, meaning Yahoo's 23 percent stake could be worth more next week than it is now. Yahoo stock pulled back from a 14-year high and fell 0.8 percent to 42.55 with 71.7 million shares traded, more than double its 10-day average of 34.2 million.
"There is some nervousness out there, so some money is coming out of the high-flyers and some of it is people getting ready to raise some cash to put to work to Alibaba," said Ken Polcari, Director of the NYSE floor division at O'Neil Securities in New York.
Heavily-traded Facebook and Netflix lost nearly 4 percent each. The S&P technology sector lost 0.6 percent as the worst performing of the 10 major S&P sectors.
Investors also exercised caution ahead of the policy statement from the Federal Reserve on Wednesday, which could provide clues on the timing of an interest rate hike. Continuación...