Yelp knows its credibility is only as good as its reviews, so today, it’s releasing its first Consumer Alerts Report, which details incidents in which Yelp’s team intervened to cut off fraudulent reviews or activity. The report shines a light on behavior that one would likely expect happens on a review site — people trying to game the system — but only focuses on successful cases where either Yelp’s human team or software detected abnormal behavior. The result of the detection is sometimes closed user accounts, but more frequently, a “consumer alert” placed on business’ pages. The company also just launched “suspicious review activity” badges this year, which is meant to indicate when it thinks reviews are associated with fake review rings.

Overall, Yelp put more than 580 consumer alerts on different business’ pages after picking up on positive reviews coming from the same IP address, and it placed more than 300 alerts on pages where Yelp was tipped that the business owner was purchasing or encouraging reviews. The company says it closed 550 user accounts this year that were associated with just one review ring that focused on creating fraudulent reviews.

In the report, the team also detailed the various reasons fraudulent reviews might be made, including political activism, fandoms acting out, and viral news stories. One-star challenge videos on YouTube, which involve people trying one-star restaurants in their area, also contribute to fake reviews being posted.

Of course, Yelp published this report to demonstrate that it takes fake reviews seriously, but it’s tough to say how large of a problem those fraudulent reviews might be. Yelp’s goal, as evidenced by this report, is to prove that its software is catching bad behavior — even more effectively than its human moderators. Still, Noorie Malik, head of user operations at Yelp, tells me that her team scours the web for indicators of fraud and is constantly hunting for fake reviews. They also get tipped off when patrons or competitors notice an establishment is encouraging reviews when people note physical signage in the establishment.

Just like any other review outlet, including Rotten Tomatoes, Apple Podcasts, and Steam, Yelp has to maintain the integrity of its platform to keep people coming back.

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