A stock or share certificate is a legal document that proves ownership of a certain number of stocks or shares in an organization. The original certificate is usually issued as proof of the transference of the shareholding.

Usually companies issue these when the organization decides to transition from a private to a public market for whatever reason that necessitated it. When this happens, the first stock offer the company makes is called an IPO or an Initial Public Offering and it can also issue more stock if it needs to. Click here to read more.