Travel / Outdoors

LONDON — Travel planning website TripAdvisor must stop claiming that all the reviews on its British site were written by independent travelers — and therefore reliable — a British regulator said Wednesday.

The Advertising Standards Authority said the claims on TripAdvisor.co.uk, including "reviews you can trust" and "more than 50 million honest travel reviews and opinions from real travelers", were misleading.

The agency said it was possible that some reviews on the website could easily have been submitted by people who were not real travelers but just trying to influence customers' choices.

TripAdvisor, based in Newton, Massachusetts, claimed it had invested in systems, processes and resources to identify and minimize fraudulent content.

It said the number of fraudulent reviews was negligible, that research showed the average traveler read dozens of reviews before making a booking and tended to discount reviews that were significantly out of line with others.

But the U.K. advertising board indicated that even the risk of a small number of fraudulent reviews means the website cannot claim they are all trustworthy.

"Because we considered that the claims implied that consumers could be assured that all review content on the TripAdvisor site was genuine, when we understood that might not be the case, we concluded that the claims were misleading," the agency's ruling said.

The ruling came in response to complaints from two hotels which were not identified and KwikChex Ltd., based in Bournemouth, England, which offers services to companies for protecting their reputations.

In a statement on its website, KwikChex said TripAdvisor does have the capability of authenticating reviews but that a "substantial number" of reviews on the site, both positive and negative, are fraudulent.

"It is small businesses that suffer most as they tend to have few reviews and so the impact is much greater," KwikChex said, "although any business with a recent very bad review does suffer, particularly if it is for example a false accusation of something such as food poisoning, bedbugs or criminality."

TripAdvisor was set up by Bellevue, Wash.-based Expedia, Inc., but was spun off as a separate company in December.