The most recognized stock exchange in the world is the New York Stock Exchange or the NYSE. There are however, many exchanges throughout the United States that all operate in a similar manner. Exchanges are dual auction markets. They provide a central market place where buyers and sellers come together in one centralized location to compete with one another. Buyers compete with other buyers to be the highest price anyone is willing to pay for the security and sellers compete with other sellers to be the lowest price at which anyone is willing to sell a security. All transactions in an exchange-listed security that are executed on the exchange have to take place in front of the “specialist” or designated marker maker for that security. The specialist / DMM is an exchange member who is responsible for maintaining a fair and orderly market for the stock in which they specialize. The specialist / DMM stands at the trading “post” where all the buyers and sellers must go to conduct business in the security. This is responsible for the “crowd” that you see on the news and financial reports when they show the floor of the exchange. All securities that trade on an exchange are known as listed securities.
The Role Of The Specialist / Designated Market Maker (DMM)