A firm is said to be a Public Joint-Stock Company when it

A firm is said to be a Public Joint-Stock Company when it sells its shares to members of the public. This means that the ownership of the company is shared among a large number of people who have bought shares in the company. This is different from a private company, where the ownership is restricted to a small group of individuals or entities. In a Public Joint-Stock Company, the shares are traded on a stock exchange, and the value of the shares is determined by supply and demand in the market. The company is also subject to regulations and disclosure requirements to protect the interests of the shareholders and the public.