DARTFORD and Gravesham NHS Trust has been warned about anti-competitive behaviour over the way it runs private patient units.
The trust, which runs Darent Valley Hospital in Dartford, was reported by a whistleblower to the Office of Fair Trading for exchanging information on pricing.
Seven other trusts, all based in the south of England, were also reported but escaped a formal investigation by giving voluntary assurances they would no longer discuss pricing.
The trusts have also agreed to train their staff in competition law.
The exchange of commercially sensitive pricing information can result in higher prices for customers as it can diminish incentives to compete on price.
The OFT has the power to impose large financial penalties when such practices are uncovered.
But in this case the regulator decided not to carry out a formal investigation as it judged the exchange of information was down to a lack of awareness.
The eight trusts involved were: Brighton and Sussex, Frimley Park, East Sussex Healthcare, Portsmouth, Dartford and Gravesham, Southampton, Epsom and St Helier and North Hertfordshire.
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