It's been part of the user review story for years - hotels worried about customers holding them to ransom with the threat of a bad review unless they get a refund or an upgrade.
Such is the potential damage to a hotel from such activity that TripAdvisor has this week launched a new feature as part of its management tools to help property owners if faced with a scenario.
The user review giant says it hears from hoteliers occasionally that a customer has threatened to write a negative review about a property "unless a demand a refund, upgrade, or other request is met".
Reporting a threat via the service's owner tools "can supplement our investigative procedure and help us keep blackmail reviews from ever reaching the site".
Owners can now directly report any threat so that a flag is put against future reviews which might look suspicious.
A guide to the new tool says:
"We take allegations of blackmail or threatening behavior by guests against property owners very seriously. This activity is strictly against our guidelines and may also be illegal in many locations."
TripAdvisor says the reporting of blackmail will only work at the time the threat is made, rather than after it appears online.
The company says "most guests" do not follow through on their threats, but it is important for owners to ensure they report all potential activity.
It also warns that it cannot guarantee that every review under question will be removed, so recommends that managers still post a response to any questionable reviews.
NB:Blackmail image via Shutterstock.