Market Maker (MM)

A market maker (MM) is a trader, trading firm, or automated system that continuously quotes both a buy price and a sell price for an asset, earning a living from the small gap between the two rather than from betting on which direction the price will move. On a centralized exchange this means resting limit orders on both sides of the order book; on a decentralized exchange it can instead mean supplying tokens to an automated liquidity pool.

The mechanic is simple. If an asset trades near $10, an MM might bid $9.95 and offer $10.05. Each time a buyer hits the offer and a seller hits the bid, the market maker pockets that $0.10 gap, known as the bid-ask spread, and repeats the process thousands of times a day. Exchanges often reward designated market makers with fee rebates or discounts, since their constant two-sided quoting keeps order books deep and tradable, which matters most for lower-volume pairs where liquidity would otherwise be thin.

Market making is not risk-free. If an MM keeps buying into a falling market or selling into a rally, its inventory can end up on the wrong side of the move, so professional firms lean on hedging and rapid order-cancellation logic to manage exposure, particularly around volatile news. Without active market makers, spreads widen, slippage increases, and smaller-cap coins become harder to trade near a fair price. Large exchanges typically run formal market maker programs with volume-based fee tiers, low-latency APIs, and sometimes credit lines to attract firms willing to keep both sides of the book tight.