Market maker

A market maker or liquidity provider is a company or an individual that quotes both a buy and a sell price in a financial instrument or commodity held in inventory, hoping to make a profit on the bid-offer spread, or turn. The U.S. Securities and Exchange Commission defines a "market maker" as a firm that stands ready to buy and sell on a regular and continuous basis at a publicly quoted price.

A Designated Primary Market Maker (DPM) is a specialized market maker approved by an exchange to guarantee that he or she will take the position in a particular assigned security, option or option index.

Most foreign exchange trading firms are market makers and so are many banks. The market maker sells to and buys from its clients and is compensated by means of price differentials for the service of providing liquidity, reducing transaction costs and facilitating trade.

Market makers that stand ready to buy and sell listed on an exchange, such as the or the , are called "third market makers." Most operate on a "matched bargain" or "order driven" basis. When a buyer's bid price meets a seller's offer price or vice versa, the stock exchange's matching system decides that a deal has been executed. In such a system, there may be no designated or official market makers, but market makers nevertheless exist.

In the United States, the (NYSE) and (AMEX), among others, have Designated Market Makers, formerly known as "specialists", who act as the official market maker for a given security. The market makers provide a required amount of liquidity to the security's market, and take the other side of trades when there are short-term buy-and-sell-side imbalances in customer orders. In return, the specialist is granted various informational and trade execution advantages.

Other U.S. exchanges, most prominently the NASDAQ Stock Exchange, employ several competing official market makers in a security. These market makers are required to maintain two-sided markets during exchange hours and are obligated to buy and sell at their displayed bids and offers. They typically do not receive the trading advantages a specialist does, but they do get some, such as the ability to naked short a stock, i.e., selling it without borrowing it. In most situations, only official market makers are permitted to engage in naked shorting. Recent changes to the rules have explicitly banned naked shorting by options market makers.

...
Wikipedia