Final answer:
The dividend that necessitates a firm to sell a part of itself is an equity financing dividend, associated with the issuance of stock. The decision to do this is made by the company's board and management and is influenced by whether the firm is private or public.
Step-by-step explanation:
The dividend that requires a firm to sell at least a portion of itself is known as an equity financing dividend. This occurs when a firm decides to issue stock to raise funds. Typically, these funds might be used to pay shareholders a direct payment in the form of a dividend, to reinvest back into the company, or for other business needs. The decision to issue stock, pay dividends, or reinvest profits is a strategic one and is usually made by the company's board of directors and management. Firms can be classified as private or public, and this classification can influence how these decisions are made and implemented.