A minority interest is a small stake in a company’s business owned by someone else. If we own all of a company and someone else owns 10 percent of the business, we only own 90 percent of the business. To own all of the business, we have to negotiate with the other party to buy out his or her minority interest. Enterprise value treats the minority interest as another debt. It must be paid by an acquirer of the whole company, just like debt or preferred stock.