If you haven’t heard about Carl Icahn, well you should, or maybe you’re not into Wall Street that much. He’s known as an activist investor, meaning he buys up lots of shares in a company and then shakes things up. Like in Blockbuster. And Yahoo. And now, Take-Two. Icahn has acquired an 11% stake in the GTA publisher, and Wall Street is already waiting for a shareholder revolt in the company.

Despite the success of GTA 4, Take-Two stock is only worth half of what it was two years ago, and since Icahn acquired the 11%, the Take-Two share has risen almost 10%. Expect some turmoil at Take-Two in the next few months.