Shares of small biotech firm Enzon (UNKNOWN:ENZN.DL) were up about 5% today after the CEO announced that Lazard had been hired to look into potentially selling some or all of the company. Carl Icahn, who has a 13% stake in the company, also met with management to discuss something similar; shares have been down since he announced that meeting in late November. In this video, Motley Fool health care analyst David Williamson tells investors what kind of influence we can expect Icahn to have on shares as the company moves toward selling.