Analysts to Icahn: Maybe check your Apple assumptions

Carl Icahn's call for Apple to buy back more shares using a tender offer was met with skepticism by many Wall Street analysts, who questioned the activist investor's assumptions about the company's growth rate and the effectiveness of another big buyback.

"There are other uses of domestic cash besides big tender offers. It's already proven itself shareholder friendly and it doesn't need to get painted into a corner by some flamboyant grandstanding," said Alex Gauna of JMP Securities.

Icahn's latest buyback demand is based partially on the premise that the company's sales will grow 80 percent over the next three years--substantially higher than recent growth--an assumption Gauna dismisses.

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"We don't know enough about new revenue streams to say that say Apple is going to meet those targets," Gauna said.

While some analysts agree with Icahn that Apple could buy back more stock, other questioned both the timing and the effectiveness of Icahn's communications strategy.

"I don't disagree with Icahn," said Oppenheimer's Andrew Uerkwitz. "They have a ton of cash. The stock is undervalued. But Apple will not listen to him. He owns one percent of the company. This feels like an Icahn strategy to keep the momentum going on in the stock."

George Young, manager of the Villere Balanced Fund (which owns Apple as one of its biggest holdings), thinks Icahn is "overly optimistic" on the likelihood of a buyback doubling the stock's value.

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"Over a long period of time, anything can double but I don't think it's quite as optimistic has he's painting. It's a great stock, great products obviously, and I think it can do well over time," Young said.

Gene Munster, analyst at Piper Jaffray, also thinks a bigger buyback would be appropriate, and that it could happen next spring.

The tech behemoth has already been buying back stock for some time, of course.

In an open letter to CEO Tim Cook published Thursday, Icahn made two key arguments: one, that the market misunderstands Apple and dramatically undervalues the tech titan; and two, that Apple should take advantage of this undervaluation and buy back more stock.

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Icahn says the exact size of the repurchase isn't the issue. "We are simply asking you to help us convince the board to repurchase a lot more, and sooner."

In response, Apple said it is already aggressively executing the largest capital return program in corporate history.

When Apple last reported results in July, the company said it had returned $74 billion to shareholders. It plans to return $130 billion.