Apple Inc's shares fell below $400 on Wednesday for the first time since December 2011, largely owing to worries about slowing demand for products like the iPhone and iPad.
Apple has lost more than 40 percent of its market value since its shares climbed to more than $700 in September and hit an all-time high of $705.07 on the day the iPhone 5 launched in the US.
According to Reuters, Apple shares slid 5.5 percent to $402.80 on Wednesday.
CNet wrote that the trigger for the sell-off was Cirrus Logic, which supplies analog and audio chips to Apple for the the iPhone and iPad.
Cirrus gave a disappointing revenue forecast, saying late Tuesday that it would record a total net inventory reserve for its fiscal fourth quarter ended March 30 of $23.3 million.
USA Today described Apple as "damaged goods with investors," pointing out that it was "just the latest piece of bad news" for the stock.
Data from IDC, a tech industry tracker, last week showed an 8 per cent dropoff in Mac shipments in the US.
USA Today also cited Jeffrey Gundlach of DoubleLine Capital as saying that Apple shares could fall to the $300s.
Financial stocks generally fell Wednesday after Bank of America posted revenue and profits that were below Wall Street expectations.