“Our worry is that millions of online shoppers could be misled by reading fake reviews and then spending their money based on those recommendations,” CMA chief executive Andrea Coscelli said in a statement.
“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,” Coscelli added.
Amazon and Google said that they would cooperate with the CMA inquiry.
An Amazon spokesperson said the company devotes “significant resources to preventing fake or incentivized reviews from appearing in our store.” The company says it prevented 200 million suspected fake reviews last year being seen by customers around the world and earlier this month filed a lawsuit against the owners of two websites mentioned in the Which? investigation.
“Our strict policies clearly state reviews must be based on real experiences, and when we find policy violations, we take action — from removing abusive content to disabling user accounts,” a Google spokesperson said.
The CMA has launched a separate investigation into Facebook looking at the same issue and last week said it is investigating Apple and Google’s dominance in mobile operating systems, app stores and web browsers.