The Nasdaq tumbled more than 2 percent on Friday as momentum stocks like Netflix and TripAdvisor sold off for a second straight session.
The big drop in momentum stocks overshadowed the day's relatively strong March jobs data, which helped the Dow and S&P 500 hit intraday record highs early in the session.
Momentum names - typically high-growth companies mostly in the tech and biotech sectors that led 2013's rally - have sold off in recent weeks but appeared to stabilize earlier this week.
Two weeks ago, a drop in Gilead Sciences' stock (GILD.O), after U.S. lawmakers asked it to explain the $84,000 price tag of its new hepatitis C drug Sovaldi, set off a wave of losses in other biotech and momentum names.
"It's a surprise how violent the selloff in some of these momentum stocks is. They have had an enormous run up, and you can come up with all kinds of things as reasons. But my sense is if you need to sell something to pay the big capital gains from last year ... they might be good candidates to sell," said Eric Kuby, chief investment officer at North Star Investment Management Corp in Chicago.
The Nasdaq biotech index .NBI was last down 3.5 percent and 1 percent lower for the week. It has dropped 17 percent since reaching a high on February 25.
On the day, Biogen Idec Inc (BIIB.O) was down 3.7 percent at $290.83, while Gilead Sciences (GILD.O) was down 2.6 percent at $72.05.
The S&P 500's top seven percentage decliners were Nasdaq names. E*Trade Financial (ETFC.O) was down 7.5 percent at $20.50, Netflix (NFLX.O) dropped 4.2 percent to $337.72 and TripAdvisor (TRIP.O) was down 7 percent at $84.93.
The Dow Jones industrial average .DJI fell 84.9 points or 0.51 percent, to 16,487.65, theS&P 500 .SPX lost 16.79 points or 0.89 percent, to 1,871.98 and the Nasdaq Composite .IXIC dropped 100.27 points or 2.37 percent, to 4,137.47.
The S&P 500 earlier touched a record high of 1,897.28, the third time this week that the index had set an intraday record, while the Dow hit an intraday record high of 16,631.63.
Stocks opened higher on optimism spurred by the nonfarm payrolls report, which showed employers added 192,000 jobs in March, just shy of the 200,000 forecast, after hiring 197,000 in February. The unemployment rate was unchanged at 6.7 percent. With a solid pace of hiring for a second month, the economy appears to be recovering from a winter slowdown.
Mylan Inc (MYL.O) rose 4.2 percent to $51.95 after a report said the company was looking to acquire Swedish rival Meda AB (MEDAa.ST). Meda, though, said on Friday that it had rejected Mylan's takeover approach. On Thursday, Mylan sued Celgene Corp (CELG.O) to stop the latter's effort to keep generic versions of two drugs that generate $4.5 billion of annual sales off the market.
Halozyme Therapeutics Inc (HALO.O) plunged 27.8 percent to $8.36 after the company said it was temporarily halting enrollment of patients and dosing of its cancer drug in a mid-stage trial on patients with pancreatic cancer, after the recommendation of an independent safety committee.
(Additional reporting by Chuck Mikolajczak; editing by Bernadette Baum, Nick Zieminski and Jan Paschal)
