A shareholder, also referred to as a stockholder, is any person, company, or institution that owns at least one share of a company’s stock (equity). Because shareholders are a company's owners, they reap the benefits of the company's successes in the form of increased stock valuation or profits distributed as dividends. If the company does poorly and the price of its stock declines, however, shareholders can lose money.
- Definition - What does Shareholder Mean? Investopedia