Three Virgin Media employees have been caught using inside information to place more than £16,000 in bets on the hit TV talent show The X Factor.
The trio were found to have abused their access to Virgin's data on voting patterns to make "unfair" bets on which contestants would be eliminated from the ITV programme last year.
The scam was unearthed by a Gambling Commission investigation, launched after bookmaker Betfair reported suspicious betting activity between October and November.
The probe, which concluded on Thursday, resulted in the bets being voided while the staff involved have been dismissed. There is no evidence that the integrity of the public voting or the shows involved were compromised, the commission said.
But the commission has consulted with Ofcom, which has been working with Virgin Media to ensure steps are taken to prevent the scam recurring.
Nick Tofiluk, the commission's director of regulation, said: "Following a multi-agency investigation led by the Gambling Commission, we are satisfied that the bets placed were substantially unfair as the individuals involved had inside information. We have worked closely with all the bodies involved to ensure that those individuals do not profit from their activity and that appropriate action has been taken to prevent a recurrence of such activity in the future."
Virgin Media described it as a one-off occurrence at the company but said extra monitoring would take place to stop it happening again.
A spokesperson said: "We take this matter extremely seriously and have been working with the Gambling Commission and Ofcom to bring this to a resolution. Following a thorough investigation, we can confirm this was an isolated incident where three individuals were found to have misused their legitimate access to internal data to identify the volume of calls being made."
Ofcom assured X Factor voters that none would have suffered financially.
Matt Cardle was crowned 2010 X Factor winner in December, polling more votes than any of his rivals on all but one of the live shows.