Flotation (shares)

Initial public offering (IPO) or stock market launch is a type of public offering in which shares of a company usually are sold to institutional investors that in turn, sell to the general public, on a , for the first time. Through this process, a privately held company transforms into a public company. Initial public offerings are mostly used by companies to raise the expansion of capital, possibly to monetize the investments of early private investors, and to become publicly traded enterprises. A company selling shares is never required to repay the capital to its public investors. After the IPO, when shares trade freely in the open market, money passes between public investors. Although IPO offers many advantages, there are also significant disadvantages, chief among these are the costs associated with the process and the requirement to disclose certain information that could prove helpful to competitors. The IPO process is colloquially known as going public.

Details of the proposed offering are disclosed to potential purchasers in the form of a lengthy document known as a prospectus. Most companies undertake an IPO with the assistance of an investment banking firm acting in the capacity of an underwriter. Underwriters provide several services, including help with correctly assessing the value of shares (share price) and establishing a public market for shares (initial sale). Alternative methods such as the dutch auction have also been explored. In terms of size and public participation, the two most notable examples of this method is the Google IPO and Snapchat's parent company Snap Inc. China has recently emerged as a major IPO market, with several of the largest IPOs taking place in that country.

The earliest form of a company which issued public shares was the case of the publicani during the Roman Republic. Like modern joint-stock companies, the publicani were legal bodies independent of their members whose ownership was divided into shares, or partes. There is evidence that these shares were sold to public investors and traded in a type of over-the-counter market in the Forum, near the Temple of Castor and Pollux. The shares fluctuated in value, encouraging the activity of speculators, or quaestors. Mere evidence remains of the prices for which partes were sold, the nature of initial public offerings, or a description of stock market behavior. Publicani lost favor with the fall of the Republic and the rise of the Empire.

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