On Tuesday, billionaire activist investor Carl Icahn's latest tweet helped Apple Inc's shares increase to 2%. The tweet read, "Had a cordial dinner with Tim last night. We pushed hard for a 150 billion buyback. We decided to continue dialogue in about three weeks."

The dinner meeting with Apple CEO Tim Cook revolved on Icahn's insistence on the tech giant buying as much as USD150 billion of its stocks back. The billionaire investor had earlier argued that Apple's shares were priced reasonably at this point in time, and Apple could benefit from the buyback opportunity. "If Apple does this now and earnings increase at only 10 percent, the stock - even keeping the same multiple currently - should trade at $700 a share," Icahn said.

An anonymouse source told Reuters that Icahn, who was unnaturally shy about revealing details of his holdings in Apple, had a stake valued at USD1 billion in the company. Apple's current market valuation is over USD400 billion.