The official betting rules for sports are set by the governing bodies of each sport and they’re designed to protect participants. Generally speaking, betting is only available on events that have been sanctioned by the governing body and bets are settled according to the official results. There are exceptions, however, such as when a team or horse is ruled a non-runner due to injury or retirement.
In baseball, for instance, any player, umpire, or club or league employee who wagers any sum on a game that they have a duty to play in is in violation of MLB Rule 21 and will be permanently banned from the Hall of Fame. The rule is posted on dugout walls and it’s also a condition of playing in the National League.
Other rules are specific to each sport but they all share some similarities such as a prohibition on the use of any device that enables an individual to gain an advantage when placing bets and the ability for customers to create more than one account. If the sportsbook deems that an individual has opened more than one account they may revoke any winnings, withhold funds and close both accounts.
When placing a bet on a live market you’ll notice that the odds are constantly changing. This is because the outcome of the bet is based on how much money is being placed on each possible result and the bookmaker’s return rate. This is known as a totalizator bet and the odds are adjusted in real time to reflect how much money is being placed on each bet.