Stock market today: Dow, S&P 500, Nasdaq fall as tech leads sell-off amid worries over frothy valuations

Tech stocks led a selloff in the first minutes of trading on Monday as doubts about high-running valuations preyed on investors sifting through the latest flurry of quarterly earnings. The tech-heavy Nasdaq Composite (^IXIC) index led losses, sinking by more than 1.4%, while the S&P 500 (^GSPC) and the Dow Jones Industrial Average (^DJI) sank by more than 1.1% and more than 0.8%, respectively. Wall Street is getting nervous that companies aren't performing well enough to justify their high-riding market ...