Since the dawn of Yelp, a handful of businesses have been accused of trying to game the system by paying for positive reviews on the site. Recently, Yelp operatives began going undercover to bust companies for this no-no, and anyone caught buying reviews will be forced to carry a badge of shame for the 90 days.

As of this morning, there were already nine (actually eight; one of the businesses has closed) pages that are flagged with a “consumer alert” badge warning readers that “We caught someone red-handed trying to buy reviews for this business.”

The company says these alerts will continue to be posted so long as businesses continue trying to break the rules.

“The bigger Yelp gets, the more incentive there is to game the system,” said Yelp’s vice president for consumer products and mobile to the NY Times. “These notices are the next step in protecting consumers.”

To bust companies, Yelp staffers posed as “elite” reviewers to see if any companies would try to buy their positive feedback. Reviews by elite Yelpers have a higher chance of getting on a business’s front page, where most people looking for details about a company get a lot of their information.

From the Times:

A pest control company offered $5 to anyone who would post a review that the business itself had written. The moving company was willing to pay $50 but wanted original copy. An appliance repair shop provided a start: “I really appreciate that the service tech was on time, the problem was solved, everything was cleaned up and he was very professional. Please add 50 or more words,” the shop suggested. It would pay $30.

A San Diego jewelry store offered $200 for a positive review, saying that it chose to game the system after it noticed some of its bigger competitors doing it.

In a blog post from this morning, Yelp says that the consumer alerts are just the beginning:

“the next step will be to let consumers know if a business has had a large number of reviews submitted from the same Internet Protocol (IP) address, which can be a helpful indicator that they lack authenticity. While the review filter already takes this type of information into account, we believe that consumers also have a right to know if this activity is going on.”

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