Market titan Facebook has led a plunge in big-name stocks on worries about a regulatory clampdown following a massive data breach at the social media site.
Tesla, Amazon, Twitter and Google parent Alphabet have also come under the cosh, sending the tech-rich Nasdaq southwards, with the index losing 0.9 percent Wednesday.
The Dow and S&P 500 also ended in the red.
There was little movement on news that the US economy had grown a lot faster in October-December than previously thought.
In Asia, Hong Kong swung through the day and was up 0.5 percent in the afternoon, following the previous day's 2.5 percent dive, while Shanghai finished 1.2 percent higher.
Tokyo ended 0.6 percent higher thanks to a weaker yen and Singapore was up more than one percent.