Apple shares finally hit $500 for the first time since since January following news that billionaire Carl Icahn invested in the company.

Apple’s stock has been on a downward trend since the beginning of this year. It wasn’t helped much by its Worldwide Developer Conference keynote, which many conference-goers felt was lacking in “wow factor.” But despite this public reaction, Icahn says Apple is “extremely undervalued.”

The billionaire, who is also currently attempting to take control of Dell, tweeted yesterday that he spoke with Apple chief executive Tim Cook and took a “large position” in the company. He also encourages Cook to hold a much bigger buyback of its stock and plans to speak with Cook again “shortly.”

Apple is already participating in a $60 billion buyback program. The company brought in $35.3 billion in revenue and beat its iPhone sales year over year with $31.2 million. Tablet sales, however, were worse year over year at $14.6 million.

Icahn’s tweets sent the company’s stock up 5 percent to $493, but investor excitement seems to have pushed the share price over the edge. The company closed at $498.50 today, though, it’s a significant enough increase from its performance for the past seven months.

AAPL Chart

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