Britain’s Competition and Market Authority is investigating whether Amazon and Google are doing enough to combat fake reviews.

Fake reviews have become an increasing problem for online platforms and shoppers alike. As online shopping has displaced brick and mortar stores, users rely on reviews more than ever. Not surprisingly, an entire industry has grown up around providing fake reviews to dupe customers into purchasing products they otherwise may not have.

The Competition and Market Authority is investing Amazon and Google to see if they’re doing enough to protect customers by combatting fake reviews, according to The Washington Post.

Both companies have said they will continue to work with the CMA and its inquiries.