Best-selling items on Amazon Marketplace show five-star reviews provided in exchange for rewards and attempts to get negative ones removed, according to an investigation by Which?.
The consumer magazine used search terms such as “bribe” and “incentive” in relation to dozens of popular products and brands to find repeated evidence of customers reporting that sellers had approached them with a view to manipulating the rating they left for the product.
Five of the nine Amazon Best Sellers product categories that Which? analysed – smartwatches, dashcams, Bluetooth speakers, in-ear headphones and surveillance video equipment – showed repeated evidence of incentivisation, it reported.
Twelve products (24%) across the top 10 best sellers in those five categories had reviews from customers stating they were being asked to post five-star reviews or alter or remove their negative feedback.
Several reported being chased by email to do so, while others said they were sent cards alongside their products requesting positive reviews in exchange for vouchers or free gifts.
Seven (58%) of those items were Amazon’s Choice listings, the platform’s recommendation label that is influenced by high ratings.
One customer told Which? he could “not believe the persistence” of one seller in trying to get his negative product review on Amazon changed or deleted.
Tim Winkle, 64, purchased a Teaisiy USB webcam last year and gave it a two-star review due to what he felt was poor quality.
The third-party seller behind the product then emailed him asking him to alter or delete his negative review in return for a £10 gift voucher. After he refused, he received a series of other offers by email over three months, reaching a peak of £50.
The latest investigation follows reports in May that Amazon had taken action to suspend the selling privileges of tech suppliers Aukey and Mpow.
Which? found numerous examples of people writing negative reviews on Amazon to shine a light on unscrupulous behaviour from sellers.
Three Peztio webcam buyers stated the seller had offered them £40 to delete their negative reports of the product, which had an overall rating of 4.2 out of five stars.
One Aswee listing for a smartwatch had two reviews from people stating they had been asked to write a positive review in exchange for a £15 voucher.
A number of Victure customers said they had been offered complimentary gifts in exchange for five-star reviews, including an SD card.
Which? has also previously uncovered evidence of fake and suspicious review activity on eBay, Facebook and Google.
The Competition and Markets Authority (CMA) announced an investigation into major websites that host reviews in May 2020.
Amazon has an anti-manipulation policy for customer reviews stating that any attempts to manipulate reviews, including by directly or indirectly contributing false, misleading or inauthentic content, is “strictly prohibited”.
Rocio Concha, director of policy and advocacy at Which?, said: “Amazon must, as an absolute minimum, do more to enforce its own policies – especially when evidence of manipulation is hidden in plain sight in its Best Sellers lists.
“The CMA needs to urgently get to the bottom of the problem of misleading and fake reviews and be prepared to take strong action to ensure consumers can trust the reviews that influence billions of pounds of spending every year.”
An Amazon spokesman said: “We are relentless in our efforts to protect the integrity of customer reviews. We remove fake reviews and take action against anyone involved in abuse. We have won dozens of injunctions against providers of fake reviews across Europe and we won’t shy away from taking legal action.
“However, Amazon and other online retailers cannot do this alone. Customers need to be able to trust the reviews they see online and the systematic manipulation of reviews needs consistent enforcement and global co-ordination, with stronger enforcement powers given to regulators against bad actors.
“We continue to work to protect the authenticity of customer reviews. We advise customers who doubt the credibility of a review on a product to click the ‘report abuse’ link available below each review. We will then investigate and take necessary measures.”
A CMA spokeswoman said: “Fake reviews are a major concern and it’s great that Which? is shining a further spotlight on this issue. A huge amount of shopping is done online, so it’s vital that people can trust the reviews they see and don’t hand over hard-earned cash for items that aren’t as expected.
“We’ve already taken action to clamp down on the trading of fake reviews and have an ongoing investigation into how platforms detect and tackle them once they make their way online. This is a high priority for the CMA and we will be updating on this work shortly.”