Carl Icahn reveals Apple stake on Twitter, says it’s ‘undervalued’

Investor Carl Icahn announced Tuesday on Twitter that he had made a large investment in Apple Inc., calling the stock “undervalued.�

The influential investor has become increasingly active in the tech sector in recent years. News that he has taken a stake in Apple predictably sent the stock soaring up $26.29, or 5.63%, to $493.65 in midday trading.

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Apple investors, who have endured a rough year as they watched the stock tumble from its all-time high last September, could barely contain their glee.

For the moment, Icahn said he is requesting that Apple Chief Executive Tim Cook and company officials pursue a bigger buyback of its stock to help raise the value. Earlier this year, under investor pressure, Apple decided to increase the size of a dividend-and-buyback program to $100 billion, including $60 billion to repurchase stock through 2015.

“We appreciate the interest and investment of all our shareholders,� Apple spokesman Steve Dowling said in an email. “Tim had a very positive conversation with Mr. Icahn today.�

But that’s apparently not enough for the aggressive investor, who has a reputation for taking large positions and then shaking up management’s approach.

Icahn told investors earlier this week to watch his Twitter account for a big announcement. Just before noon PDT, he posted these two tweets:

The announcement immediately triggered a big reaction on Twitter.

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