This "fake and incentivised" industry uses Facebook and Twitter to find people to give five-star ratings to mediocre products sold on Amazon (AMZN) in order to give them a higher overall rating in return for free items.
Fake review groups on Facebook with hundreds of thousands of members between them were found to be using the site to get fake positive ratings for tens of thousands of products across more than 130 brands posted on Amazon.
Trading, or facilitating the trading of, fake reviews, is likely to be in breach of consumer law. The Competition and Markets Authority (CMA) first started examining the problem in 2019 but sites such as Facebook have failed to bring an end to this kind of activity, with implications for consumer trust in online reviews.
The UK government has also proposed measures to tackle the trading of bogus reviews as part of its consumer and competition reforms.
Offering free products in exchange for five-star reviews is also against Amazon’s terms and conditions.
The investigation, carried out between June and November 2021, found that is was easy to find and join fake review groups on Facebook by looking up key terms such as “Amazon five star review” and “free AMZ” in the search bar.
Facebook sometimes responded with a message warning that the term was associated with fraudulent activity. However, users are able to simply click continue to carry on searching. This "raises questions about how effective such warning messages are", according to Which?
Some 18 Facebook groups with a total of over 200,000 members were found to be trading false reviews. Some of the groups had been on the social media platform since 2011, despite Facebook having made several commitments to the CMA, announced in January 2020 and April 2021, that it would take action on this type of activity on its site.
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The investigators found that after joining the groups they were offered hundreds of free Amazon items ranging from hats and gloves to headphones, webcams, fairy lights, birthday balloons and dog beds in exchange for five-star reviews.
Agents claiming to be acting on behalf of Amazon Marketplace sellers shared spreadsheets and documents of items that researchers could review, and asked them to choose which products they wanted.
The agents, often based in China, India and Pakistan, posted pictures of items that they said they needed five-star reviews for. They often used easily decipherable cryptic messages in an attempt to evade detection, such as: “Ne3d R3vi3w Full Fr33 product”.
Agents also advertised "free Amazon products" on Facebook Marketplace and shared QR codes within Facebook groups to draw potential reviewers on to other messaging platforms.
Which? bought and reviewed four of the items on offer and found that none of them deserved the five-star rating that the agents were asking for, giving them all two or three star ratings.
This meant that none of the agents would reimburse Which?’s researchers for the purchases, and they each tried to pressure them to change their reviews to five-star, telling them that was the only way to get their money back.
One of the agents said they would only earn commission themselves for achieving five-star reviews.
Which? is calling on Facebook to explain why such activity still appears to be rife after previously committing to taking action to get rid of fake review trading.
A spokesperson for Meta, Facebook's new name, said: “Fraudulent and deceptive activity is not allowed on our platforms, including offering or trading fake reviews.
"We proactively removed many of the groups identified by Which? before they approached us, and we swiftly removed the additional groups that violated our policies.
"We’ve been working collaboratively with the CMA to tackle this across our platforms — and Which? research confirms that those measures have been effective. In the last year, we have removed more than 16,000 groups that were trading in fake and misleading reviews.
"While no enforcement is perfect, we continue to invest in new technologies and methods to protect our users from this kind of content.”
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Twitter is also a hotbed for fake review activity, according to a separate Which? investigation in October 2021.
Which? researchers used a fake Twitter profile to pose as a potential Amazon product reviewer and searched for phrases such as "Amazon freebies", "Amazon free product seller for good reviews" and "free Amazon products for review" – finding dozens of fake review agents working on the platform.
Of the 30 agents contacted through Twitter, 19 responded to the investigators and dozens of other agents also followed Which?’s fake Twitter profile page within a few weeks of its first tweet being posted about wanting to become an Amazon product reviewer.
A total of 53,065 listings and 132 brands were sent to the researchers by the agents on Twitter. Products included beauty items, children’s toys, clothing, earbuds, fake hair, smartphone cases, stationery and underwear.
Which? specifically liaised with the review agents about dozens of items and found that at least seven had earned the coveted Amazon’s Choice endorsement.
The majority of profiles said they were based in China. Others appeared to be based in India, Pakistan and the USA and were looking for reviewers in countries including Australia, Canada, France, Germany, Italy, Japan, Mexico, the Netherlands, Russia, Saudi Arabia, Spain, Sweden and the UAE.
Twitter suspended three profiles from Twitter for "violating" rules before they were flagged as part of the investigation. However, many profiles remained active until Which? notified Twitter. One profile showed up as having been live since November 2017. Twitter said it has since suspended these profiles.
A Twitter spokesperson said: “We want Twitter to be a place where people can make human connections, find reliable information, and express themselves freely and safely.
"To make that possible, we do not allow spam or other types of platform manipulation. We define platform manipulation as using Twitter to engage in bulk, aggressive, or deceptive activity that misleads others and/or disrupts their experience.
“Using both technology and human review, we proactively and routinely tackle attempts at platform manipulation and mitigate them at scale by actioning millions of accounts each week for violating our policies in this area. We are constantly improving Twitter's auto-detection technology to catch accounts engaging in rule-violating behaviour as soon as they pop up on the service.
“We’ve suspended all the referenced accounts for violations of the Twitter Rules.”
Some £23bn a year of consumer spending is influenced by online reviews, according to the CMA.
Which? is calling on the CMA to investigating Twitter over incentivised and fake reviews.
The consumer group wants the CMA to challenge Facebook to "provide evidence to show that the action it is taking is effective. Otherwise, stronger action should be taken against the platform to ensure that consumers’ trust in online reviews does not continue to be undermined".
Which? is also calling on the government to bring forward legislation to address the trading of fake reviews as soon as possible.
Rocio Concha, Which? director of policy and advocacy, said: “Facebook and Twitter are failing to adequately tackle fake review factories on their platforms, making it easy for unscrupulous firms and fake review agents to evade weak checks by some of the biggest online platforms and shopping sites. This risks seriously undermining consumer trust in online reviews.
“Facebook must prove that it is taking effective action having repeatedly made commitments to the regulator that it would crack down on fake review trading. The CMA should also consider investigating Twitter over this issue.
“The government plans to tackle fake reviews as part of its consumer and competition reforms and should bring forward new laws to banish these exploitative practices as soon as possible.”
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