<P> A public offering is the offering of securities of a company or a similar corporation to the public . Generally, the securities are to be listed on a stock exchange . In most jurisdictions, a public offering requires the issuing company to publish a prospectus detailing the terms and rights attached to the offered security, as well as information on the company itself and its finances . Many other regulatory requirements surround any public offering and they vary according to jurisdiction . </P> <P> Initial public offering (IPO) is one type of public offering . Not all public offerings are IPOs . An IPO occurs only when a company offers its shares (not other securities) for the first time for public ownership and trading, an act making it a public company . However, public offerings are also made by already - listed companies . The company issues additional securities to the public, adding to those currently being traded . For example, a listed company with 8 million shares outstanding can offer to the public another 2 million shares . This is a public offering but not an IPO . Once the transaction is complete, the company will have 10 million shares outstanding . Non-initial public offering of equity is also called seasoned equity offering . </P> <P> A shelf prospectus is often used by companies in exactly that situation . Instead of drafting one before each public offering, the company can file a single prospectus detailing the terms of many different securities it might offer in the next several years . Shortly before the offering (if any) actually takes place, the company informs the public of material changes in its finances and outlook since the publication of the shelf prospectus . </P>

What different forms of securities can public ltd company issue