Advertisers love live sports. But good luck measuring that investment.

Although tides of ad revenue flow based on the ratings of certain tentpole TV events, a new crop of scammers now operate illicit sports livestreaming rings, and there’s almost nothing broadcasters can do about it.

According to a new report released Tuesday by ad tech auditing and analytics startup Adalytics, illicit livestream sports services, such as WatchSports and StreamSports99, are distributing unauthorized individual streams of high-profile sporting events to hundreds of thousands of devices in some cases.

In one example, Adalytics observed a single individual stream of the Super Bowl on NBCU’s Peacock distributed to more than 100,000 devices. That was just one of more than 100 other sites redistributing livestreams of the game as well.

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