What is "Listing" of Stocks

All exchanges have initial listing requirements that companies must satisfy before they can be listed on a particular exchange. and traded there, but requirements vary by stock exchange:
Since an exchange makes money by charging commissions or fees on trades, most requirements are designed to ensure that a certain amount of trading will occur in the company’s shares. In most cases, larger companies have more trading activity, and so several requirements are related to ensure a minimum size. The most common requirements are a minimum market value, a minimum income and revenue, a minimum number of shares outstanding, and a minimum number of holders of public stock.

Although most stocks listed on an exchange are listed stocks for that exchange, an exchange can list the securities of any other exchange, if it so chooses. To increase pricing competition, the Securities and Exchange Act of 1934 contains a provision referred to as unlisted trading privileges (UTP) that allows any exchange to list any securities listed on any other exchange.

•     Bombay Stock Exchange: Bombay Stock Exchange (BSE) has requirements for a minimum market capitalization of Rs.250 Million and minimum public float equivalent to Rs.100 Million.

•     London Stock Exchange: The main market of the London Stock Exchange has requirements for a minimum market capitalization (£700,000), three years of audited financial statements, minimum public float (25 per cent) and sufficient working capital for at least 12 months from the date of listing.

•     NASDAQ Stock Exchange: To be listed on the NASDAQ a company must have issued at least 1.25 million shares of stock worth at least $70 million and must have earned more than $11 million over the last three years.

•     New York Stock Exchange: To be listed on the New York Stock Exchange (NYSE) a company must have issued at least a million shares of stock worth $100 million and must have earned more than $10 million over

Only members of an exchange may list and execute trades at the exchange. When a retail investor wants to trade an exchange-listed stock, he must go to a broker. If the broker is a member of the exchange where the stock is listed, then she can send her client’s order to a representative of her firm, who will then execute the trade. However, if her firm is not a member, then she will have to send the order to another broker or dealer who is a member of the exchange or to their representative at the exchange.

Buy or sell limit orders are entered into the system and crossed with matching orders. If there are no matching orders, then they are queued, first by price, then by date, as a bid or offer price. The list of all bids and offers constitutes the order book, and the current market quote is the best bid and offer.