U.S. stocks fell, with the Nasdaq Composite Index sliding the most in two months, after large technology stocks from Google Inc. to Yahoo Inc. plunged as investors sold the bull market’s biggest winners.

Google Class A shares sank 4.6 percent in the biggest drop since October 2012. Facebook Inc. lost 4.6 percent, bringing its two-day slide to 9.5 percent. Yahoo Inc. declined 4.2 percent to the lowest since November. An index of biotechnology stocks plunged 4.1 percent. GrubHub Inc. surged 31 percent in its trading debut.

The Nasdaq index lost 2.6 percent to 4,127.73 at 4 p.m. in New York, for its worst day since Feb. 3. The Standard & Poor’s 500 Index sank 1.3 percent to 1,865.09 after earlier rising to an all-time high. The Dow Jones Industrial Average dropped 159.84 points, or 1 percent, to 16,412.71.

“This has been in the making for a few weeks,” Rick Fier, director of equity trading at Conifer Securities LLC in New York, said a phone interview. “Managers were positioned very heavily last year with the winners. They killed in 2013 and money started to pour in them. Today is kind of like the panic day that they couldn’t stand it any more and now they’re just puking these names.”

David Fuller's view

These market developments are discussed below, albeit less colourfully.