What does courtsiding mean in sports betting?

What does courtsiding mean in sports betting? So, why are we here at a tennis court in the middle of Sussex? We're here to see courtsiding today. Courtsiding is basically cheating. It's getting on a point before the umpires press the button and the bookmakers have applied their in-play delay. That was Joe, a professional gambler and courtsider, on the BBC's Can You Beat the Bookies? He sits at live tennis, and the moment a point ends, a partner bets on it before the umpire's score reaches the sportsbooks. He says he works about 35 weeks a year. Relaying what just happened at a live event — the point, the goal, the final out — from inside the venue to a bettor or syndicate faster than the official data feed and the broadcast delay carry it. So in-play bets land at prices that have not caught up yet. The result is not altered; the information is simply early. Named for tennis, where the gap between the court and the live line is widest. In plain terms: someone in the seats sees the point end a few seconds before the TV and the sportsbook do, and a partner bets on what already happened, at a price that is still quoting the old score. “He was courtsiding the whole second set. The book voided every ticket and closed the account.” Let's use this example. Melbourne, January 2014. A twenty-two-year-old Briton is arrested in his seat at the Australian Open with a device stitched into his shorts and wired to a phone. Reports put his head start at about ten seconds. Here is why ten seconds matters. The point ends on court at zero. His signal lands about one second later. The sportsbook's official feed catches up a few seconds after that, and only then does the live price move. The broadcast shows the point five to eight seconds after it happened. Every in-play bet accepted inside that gap was priced on a score that was already wrong. He was charged under Victoria's brand-new law, which carries up to ten years in prison. The charge was later dropped. In 2017 a man thrown out of the US Open for courtsiding the year before came back and was arrested for trespassing. And in 2020 a Spanish player, Gerard Platero, got a four-year ban, the first player ever sanctioned for it. Courtsiding breaks the ticket terms at almost every major event, and in some places it has led to arrests under betting-integrity laws. Books void the bets and close the account. The in-play delay and the market suspensions you see are their defense. Lines move and books differ. Nothing here is a guarantee or a command to bet — it's how the number works.