Has three meanings. Equity is the opposite of debt and represents the residual economic ownership or claims in a company after the claims of all creditors have been satisfied. Common stock and preferred stock are each classified as an equity security. From an accounting perspective, equity (or stockholders' equity) is a company's net worth (i.e., the difference between a company's assets and its liabilities). From a corporate finance perspective, the equity value of a company is the total value of its capital stock (i.e., the sum of the value of all classes of common stock and preferred stock).