electronic matching system

An order matching system or simply matching system is an electronic system that matches buy and sell orders for a stock market, commodity market or other financial exchanges. The order matching system is the core of all electronic exchanges and are used to execute orders from participants in the exchange.
Orders are usually entered by members of an exchange and executed by a central system that belongs to the exchange. The algorithm that is used to match orders varies from system to system and often involves rules around best execution.
The order matching system and implied order system or Implication engine is often part of a larger electronic trading system which will usually include a settlement system and a central securities depository that are accessed by electronic trading platforms. These services may or may not be provided by the organisation that provides the order matching system.
The matching algorithms decide the efficiency and robustness of the order matching system. There are two states for a market: continuous trading where orders are matched immediately or auction where matching is done at fixed intervals. A common example when a matching system is used in auction state is at the market open when a number of orders have built up.

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