Bet exchange

A betting exchange is a marketplace for customers to bet on the outcome of discrete events. Betting exchanges offer the same opportunities to bet as a bookmaker with a few differences. You can buy and sell the outcome, you can trade in real-time throughout the event and you trade out to cut your losses or lock in profit. Bookmaker operators generate revenue by offering less efficient odds. Betting exchanges normally generate revenue by charging a transaction fee.

The first betting exchanges were flutter.com and Betfair who merged in early 2000 (now Paddy Power). Betfair has maintained a dominant marketshare. BETDAQ, the second largest Betting Exchange, accounts for 7% of the betting exchange market. BETDAQ is the trading name of Global Betting Exchange Alderney (GBEA). GBEA was acquired by Ladbrokes PLC in February 2013.

Most exchanges make their money by charging a commission which is calculated as a percentage of net winnings for each customer on each event, or market. Gamblers whose betting activities have been restricted by bookmakers (normally for winning too much money) are able to place bets of unrestricted size as long as one or more opposing customers are willing to match their bets. The odds available on a betting exchange are usually better than those offered by bookmakers, in spite of the commission charged, because there are smaller overrounds.

In spite of these advantages, exchanges currently have some limitations. Because exchanges seek to concentrate their liquidity in as few markets as possible, they are not currently suited to unrestricted multiple parlay betting. Betfair does offer accumulators but these are limited in number and type: users cannot determine the outcomes contained in accumulators themselves. Some exchanges such as BETDAQ also offer multiples but the exchanges act in the same manner as traditional bookmakers in doing so (i.e. they themselves and not a customer act as the layer of such bets). Exchanges also tend to restrict the odds that can be offered to between 1.01 (1 to 100) and 1000 (999 to 1).

Traditionally betting has occurred between a customer and a bookmaker where the customer 'backs' (bets that an outcome will occur) and the bookmaker 'lays' (bets that the outcome will not occur). Betting exchanges offer the opportunity for anyone to both back and lay.

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Wikipedia