The Exchange Rules apply to all bets placed on Betfair's Exchange markets. The Exchange Rules also apply to Betfair's Exchange 'Multiples' product (see the. Betfair is a betting exchange - an online marketplace for punters to bet against themselves on sporting and cultural events around the world. Customers bet. Shares in both Betfair and Paddy Power surged on Wednesday after news of the proposed merger between the two betting companies. WELCOME TO THE APP DIRECTORY Read more Enhance your Exchange experience by using Apps. The history of online betting exchanges centres around the launch and subsequent growth of Betfair, and any examination of why betting exchanges are so popular today requires a telling of the story of Andrew Black, the grandson of Conservative MP Sir Cyril Black, who was - believe it or not - a lifelong campaigner against gambling. For the first time, anyone wishing to place a bet could carefully identify misperceptions of probability, and then benefit by removing or mitigating those misperceptions. Having hit the milestone of more than three million customers by , Betfair listed on the London stock exchange, in a move hailed as "an important landmark" by Ed Wray. How to win and make money on Betfair What is Lay Betting?