Who is considered a shareholder?

A shareholder is defined as someone who owns a portion of a company's shares or stock, which represents their ownership interest in the corporation. This ownership can grant the shareholder various rights, including the ability to vote on corporate matters and to receive dividends, depending on the type of shares they hold.

The concept of shareholders is fundamental in corporate finance, as they provide the necessary capital for companies to grow and operate in exchange for equity ownership. This means that shareholders have a vested interest in the company's performance and profitability, which can lead to an increase in the value of their shares.

The other options do not represent ownership in a company. Renting equipment is a service transaction, buying products relates to consumer behavior, and being an employee involves a contractual relationship that does not confer ownership of stock. Thus, the defining characteristic of a shareholder is ownership of stock, making the correct answer the one that identifies this relationship.