Buyers of used cars could be in line to receive compensation as advertising authorities clamp down on cars improperly labelled and sold as second-hand when the previous owner was a rental firm or other multiple-driver fleet.
Up to 100% of the car's value could be rewarded to misled consumers, depending on the details of the case.
The Times reports that the Advertising Standards Authority (ASA) will warn manufacturers and dealers in the coming weeks not to mislabel such cars.
Hundreds of thousands of consumers are potentially affected, having not been told that their cars, often advertised as having one previous owner, were formerly rental cars or fleet cars.
Last year, Fiat Chrysler Automobiles (FCA) and Alfa Romeo were chastised by the ASA for this reason, having sold two cars that had been used for contractor training and company car purposes.
The ASA asserted that cars from these sources "were more likely to have been subjected to wear and tear". FCA subsequently revealed that interim measures had already been set up to stop the practice.
Campaign group Used Car Scandal, set up by the man who brought the case against FCA, has received around 200 further cases of this type,
Following the FCA ruling, the ASA released the following statement: "If you're a fleet operator selling ex-business-use vehicles, the ASA will expect information about the ex-fleet nature of the vehicle to be included in your advertising.
"This is because it considers it to be material information that would influence a consumer's transactional decision in purchasing a vehicle. Furthermore, if an ex-business use vehicle was used by multiple users while part of your fleet, that is also likely to be considered material information that must be disclosed in the ad."
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