* Google shares dip, executive to sell nearly half his stake
* Celgene up as regulator approves new drug
* Dow off 0.3 pct, S&P down 0.1 pct,, Nasdaq off 0.2 pct,
By Rodrigo Campos
NEW YORK, Feb 11 U.S. stocks slipped at the open on Monday, with the S&P and Nasdaq dipping from multiyear highs, as Google shares weighed on the market on plans by its former chief executive to sell a large chunk of his stake in the Internet company.
Trading volume was relatively low, which could make the market volatile and exaggerate moves.
Google fell 0.9 percent at $777.94 after the company said in a filing former chief executive Eric Schmidt is selling roughly 42 percent of his Google stake, a move that could potentially net him $2.51 billion.
The decline was partly offset by gains in Apple, up 1.2 percent at $480.78 after a New York Times report that the iPhone maker is experimenting with the design of a device similar to a wristwatch.
No economic data or major earnings reports are scheduled for Monday, but Federal Reserve Vice Chair Janet Yellen is due to speak about the economic recovery at 1 p.m. (1800 GMT).
Upbeat U.S. and Chinese data last week helped the S&P 500 extend its weekly winning streak to six. The benchmark is up more than 6 percent so far this year after a steep rally in January that has stalled as the S&P and Dow industrials near record highs.
The large market rally so far this year has created space for hesitation in the absence of clear catalysts, according to Steve Goldman, principal at Goldman Management in Short Hills, New Jersey.
"Some positives behind the market rally are still there, and the path of least resistance is likely to be higher," he said.
The Dow Jones industrial average fell 35.39 points or 0.25 percent, to 13,957.58, the S&P 500 lost 1.94 points or 0.13 percent, to 1,515.99 and the Nasdaq Composite dropped 5.75 points or 0.18 percent, to 3,188.12.
US Airways shares edged up as people familiar with the matter said an $11 billion merger with AMR Corp appeared closer. The deal would create the world's largest airline by passenger traffic.
Opposition grew to the $24.4 billion buyout of Dell Inc , the No. 3 personal computer maker, as three of the largest investors joined Southeastern Asset Management on Friday in raising objections. Dell said in a regulatory filing it had considered many strategic options before opting to go private in a buyout led by Chief Executive Michael Dell.
Dell shares hovered near $13.65, the buyout offer price.
Regeneron Pharmaceuticals Inc shares jumped 8 percent to $179.11 after Sanofi said it plans to buy Regeneron's common stock.
Our top photos from the last 24 hours.