Amazon and Google are being investigated by a UK regulator over fake reviews on their sites

• A UK regulator is investigating whether Amazon and Google have done enough to stop fake reviews.
• The CMA said it's looking into whether Amazon and Google have failed to protect shoppers.
• Amazon recently urged social-media firms to help it prevent fake reviews on its site.

Britain's competition regulator has opened a formal investigation into Amazon and Google over concerns the tech giants have not done enough to combat fake reviews on their sites.

The Competition and Markets Authority (CMA) said Friday that it would now gather further information to determine whether the firms may have broken consumer law by taking insufficient action to protect shoppers from fake reviews.

The move comes after an initial CMA investigation, which opened in May 2020, and assessed several platforms' internal systems and processes for identifying and dealing with fake reviews.

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The regulator said it was also concerned that Amazon's systems had failed adequately to prevent and deter some sellers from manipulating product listings, through for example co-opting positive reviews from other products.

Some merchants are also buying fake reviews "in bulk" online, according to a February report by Which. One fake-review site offered 1,000 reviews for $11,000, while another said it could help Amazon sellers achieve the coveted Amazon's Choice status within just two weeks. Some sites asked for free or discounted products in exchange for reviews.

Groups selling Amazon reviews have also popped up on social-media sites such as Facebook and Telegram. In a blog post last week, Amazon said that social-media firms needed to spend more money helping it root out "bad actors" who use their platforms to gather fake reviews.

Insider spoke to some of the fake reviewers in February, including one who had a product refunded after deleting a negative review she had left. Another compared the fake-review phenomenon to mystery shopping.

"Our worry is that millions of online shoppers could be misled by reading fake reviews and then spending their money based on those recommendations," Andrea Coscelli, CEO of the CMA, said.

"Equally, it's simply not fair if some businesses can fake 5-star reviews to give their products or services the most prominence, while law-abiding businesses lose out."

Amazon told Insider that it devotes "significant resources" to preventing fake or incentivized reviews from appearing on its site.

"We work hard to ensure that reviews accurately reflect the experience that customers have had with a product," a spokesperson said. "We will continue to assist the CMA with its enquiries and we note its confirmation that no findings have been made against our business. We are relentless in protecting our store and will take action to stop fake reviews regardless of the size or location of those who attempt this abuse."

Amazon said in February that it analyzes more than 10 million reviews each week. It reportedly removed 20,000 product reviews in September after a Financial Times investigation suggested that some of the site's top UK reviewers may have profited from leaving positive ratings.