Carl Icahn Teases Web With Plan To Reveal Open Letter To Apple CEO Tim Cook

Carl Icahn, founder of Icahn Enterprises and billionaire activist investor, tweeted Wednesday afternoon he will pen an open letter to Apple CEO Tim Cook the following day.

"Tmrw we'll be sending an open letter to @tim_cook. Believe it will be interesting," Icahn's tweet read.

Icahn's stake in the company totals $4.4 billion, after he disclosed last May that he invested $1.65 billion into the iPhone 6 maker.

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Icahn's recent vague message followed a tweet patting his organization on the back for believing in Apple last year.

"Just over 1 yr ago we tweeted our large position in $AAPL & belief the company extremely undervalued. Since then, stock is up 50.6%" the tweet read.

Icahn tweeted last year about his large stake in Apple and his belief that the stock was "extremely undervalued." He added he had the opportunity to speak with Cook where he urged him for a larger share buyback. Investors sent Apple shares up 5 percent following that series of tweets.

Icahn then held off on his push after Apple revealed in February it bought $14 billion worth of its own stock in just a few weeks. This was the largest repurchase on record for such a short period. Icahn reacted by saying further action was not needed given that Apple was "close" to their proposed target.

It is unclear what Icahn wants from Cook this time around.

"Carl is a very aggressive and innovative investor who has absolutely no filters or any hesitation to take what he wants," said Douglas Grosfield, president and CEO of Xylotek Solutions, an Ontario-based solutions provider. "I can only imagine what a letter like that might contain. He tends to not pull any punches. That's pretty interesting considering his level of investment in a lot of tech firms. I think it'll definitely be an interesting read. It's probably going to be a frank expression of Carl's opinion of Apple since Cook took over, but playing devil's advocate here, it could be a ploy on his part to show his support for him."

PUBLISHED OCT. 8, 2014