Apple tumbled on concern that demand for the iPhone 5 is waning.
The Dow Jones industrial average edged up six points to 13,494 shortly before noon Monday.
The S&P 500 fell three points to 1,469. The Nasdaq composite index fell 14 points to 3,111.
The Standard and Poor's 500 closed at a five-year high of 1,472 on Thursday, following a solid start to the fourth-quarter earnings reporting period and amid optimism that the outlook for global growth is brightening.
Apple slid $16 to $504.10 after The Wall Street Journal reported that the company has cut its orders for iPhone 5 components due to weak demand.