Wall Street Journal (WSJ) reports that angel investor Carl Icahn bought additional stake in Apple today. By announcing his investment via Twitter today, Icahn managed to influence investors to move Apple's current share price up, as he believes that the company is "extremely undervalued".

The tweet saw a 4.8% rise in the Cupertino-based tech company in share price to USD489.57. The share price also jumped to a record intraday high not seen since January 23 which was USD494.66.

Icahn and company accumulated an estimated USD1.5 billion in ownership shares over the past month, another source told Bloomberg. Icahn has also talked with Apple CEO Tim Cook about his preference for a stock buyback as opposed to earning dividends. Buy backs increase earnings per share through reduction of outstanding shares. And with a stock market valuation nearing USD450 billion, Icahn isn't to shy away on pressuring Apple for the sake of his investment. He is known to purchase large stock in different companies and push for reform, notes WSJ.