Customer reviews have become central to online commerce, playing a huge role in determining which products succeed or fail on Amazon and other sites. A study by Northwestern University’s Spiegel Research Center found that nearly 95% of shoppers read online reviews before making a purchase.

But the authenticity of some Amazon customer reviews is coming under new scrutiny after a data leak exposed unidentified sellers coordinating to pay customers for fraudulent reviews. Products from device makers Aukey, Mpow and Tomtop were removed from Amazon after these reports surfaced.

"One of my complaints about Amazon is their inconsistency in enforcing their own terms of service. So I was really happy about the news," said former Amazon seller Jason Boyce, founder and CEO of Avenue7Media, co-author of the "The Amazon Jungle," and resident expert on GeekWire's Day 2 podcast.

"If they're not cleaning up bad behavior, violations of terms of service, it has a negative impact on the Amazon shopper," Boyce said. "If the shopper is reading and relying on reviews, and two-thirds of them are fake five-star reviews or even a third of them and they get this product and it's bad, that's bad for the Amazon customer."

Amazon "has proven over and over again" that they will go after people and companies behind pay-for-review systems, said Jeff Cohen, vice president of Marketing for Seller Labs, a company that offers software, tools and services for Amazon sellers to market their products and communicate with customers.

"Offering incentives for reviews is not something new or exclusive to Amazon," Cohen said. "But Amazon has to protect itself in a different way because it's looked at in a different way than others are in the space."

Amazon declined to comment on the specifics of the story involving Aukey and others, but said it's "relentless" in its efforts to police customer reviews, with "long-standing policies to protect the integrity of our store, including product authenticity, genuine reviews, and products meeting the expectations of our customers."

"To do this, we use powerful machine learning tools and skilled investigators to analyze over 10 million review submissions weekly, aiming to stop abusive reviews before they are ever published," an Amazon spokesperson said via email.

Amazon said it takes "swift action" against violators, including suspending or removing selling privileges: "We take this responsibility seriously, monitor our decision accuracy and maintain a high bar."

We’re tracking the latest twists in the world of Amazon reviews on this episode of Day 2, GeekWire’s podcast about everything Amazon, with insights from Cohen and Boyce.

See GeekWire's Day 2 show page for more.

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