Customer review sites are a useful way to find out about products and services, and for the businesses themselves they can be a valuable source of publicity. But a number of spam reviews sweeping the web are damaging local firms who depend on them to help make or break their reputation.
Before the evolution of the web, a friend's recommendation was a reliable and trustworthy way to find out who to call for a particular product or service.
Gary Beal was the victim of a fake and malicious review
Nowadays, many people use the wide range of review tools available online, such as company websites and review forums, to help them decide where to go for a particular service.
Photographer Gary Beal is one of many small business owners who relies on such reviews to drum up business.
"When you first start a business the thing you're looking for most is exposure, so if you put your website up onto something like local businesses by Google Maps, you expect people to go and look," he says.
His first ever review came on the Google maps site. The review appeared to have been posted by a local company, Cream Photography, in a clear attempt to steal his customers and damage his reputation.
"If it's a bad review and it's the only one there, the competition is so stiff, no-one's going to pick up the telephone," says Mr Beal.
The Wimpennys found spam reviews being posted in their name
It claimed that Mr Beal's prices were too expensive and that it could provide a better service.
Mr Beal e-mailed Cream Photography to complain about the accusations, only to find that the review was fake.
Cream Photography, run by husband and wife team Charles and Carolyn Wimpenny, denied posting any comments on Google Maps.
Over the course of that day, 100 reviews identical to the one Mr Beal had received had appeared about other companies. All, apparently, posted by Cream Photography.
Yet the Wimpennys were oblivious to the fact that harmful reviews were being posted under their name.
More frustratingly, they were unable to do anything about it.
Powerless to act
Google advised the Wimpennys that they would need to pursue the case in a US court, a long process which the couple decided would be too costly.
Google says it uses software to automatically detect spam reviews - but despite this 100 identical fake reviews were posted in the space of 24 hours.
Chris Emmins and Glen Collins on how to deal with fake online reviews
Google said in a statement that it is working to improve the system. But, that it wanted to balance identifying spam without removing genuine comments.
Website users are invited to flag spam reviews, and it was by going through the reviews themselves that the Wimpennys eventually got most, but not all, of the reviews removed.
Many businesses claim that their requests to have fake reviews removed have been ignored, leaving them feeling powerless to stop the reviews appearing against their name.
Innovating to beat the spammers
Chris Emmins of Kwikchex, a website which helps companies to remove fake reviews, is critical of Google.
"Google have provided this resource - you would think that with all their billions, they could pick up on something like that. But apparently not.
"If Google want to use reviews, they have to do a little more than they're doing, because this is child's play to pick up," he adds.
Google says it is looking to improve its system of detecting spam reviews.
He explains that many victims know who the perpetrator is, "a personal attack, say, from an ex-employee."
Mr Emmins suggests the introduction of a traffic light system as a way of grading reviews: "The more information a reviewer gives to verify their comments, the more credibility the review is awarded," he says.
The Review Centre, a website which encourages a community of reviewers to rate and slate many types of products, also has to deal with its fair share of bogus comments.
"One of the ways that our pattern checker works is that it looks at the computer address the review was written from, and if for example that address has written five other reviews for the same item that will be flagged up as suspicious," said Glen Collins, head of The Review Centre.
"If you write something which is written in a similar way - same punctuation, same grammatical errors - to other reviews, that will be picked up."
He says anything suspicious is picked up "and put into a pen for us to check."
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