S&P Dow Jones Indices said it's making the move in response to a planned stock split for Visa, another member of the 119-year old barometer of the stock market.
After its four-to-one stock split, Visa will wind up with a lower price. S&P said that would reduce the weight of the information technology sector in the Dow. Adding Apple will help balance out this reduction. Unlike other stock-market measures, the Dow weighs members by their prices, so a large change in the price of one stock can have a big effect on the overall index.
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S&P said swapping Apple for AT&T won't alter the Dow's level.
The last big shake-up came in September, 2013 when Goldman Sachs, Nike and Visa knocked out Alcoa, Bank of America and Hewlett-Packard.
Apple's stock rose $2.55, or 2 percent, to $128.99 in early trading on Friday. AT&T sank 46 cents, or 1.4 percent, to $33.54.