Professor Carolyn Roberts v Severn Trent Water Limited & Severn Trent Plc & Ors

Water Industry Act 1991 section 18(8) excludes a remedy where the contravention of an appointment condition is an essential ingredient of the claim. The enquiry is purposive and realistic. A claimant cannot avoid the exclusion by presenting the breach as mere background where the alleged abuse depends on inaccurate regulatory reporting required by the statutory regime. Misleading a regulator is not a freestanding head of abuse. The conduct must amount to abuse of a dominant position capable of affecting trade, assessed in its factual context. For a statutory water monopoly, inaccurate pollution reporting was fundamental to the alleged manipulation of price controls and consumer overcharging. The competition claims were therefore barred.

Professor Roberts sought a Collective Proceedings Order under section 47B(4) of the Competition Act 1998 for opt-out claims against six water and sewerage undertakings. She alleged that pollution incidents had been under-reported to the Environment Agency and Ofwat, causing inflated revenue allowances and higher consumer charges.

The Competition Appeal Tribunal refused the order, holding that the claims were excluded by section 18(8) of the Water Industry Act 1991: [2025] CAT 17. The appeal concerned whether the remedies sought for abuse of dominance were available otherwise than by virtue of the reporting contraventions, and whether information supplied through the Environment Agency altered that analysis.

The majority, Sir Geoffrey Vos MR and Falk LJ, dismissed the appeal. Zacaroli LJ dissented and would have allowed it.

1. Section 18(8) of the Water Industry Act 1991 excludes remedies available by virtue of an act or omission constituting a contravention of an appointment condition. Following the guidance in United Utilities Water Ltd v Manchester Ship Canal Co Ltd (No 2) [2024] UKSC 22, the relevant question is whether the contravention is an essential ingredient of the claim. Remedies independently available in respect of the same act remain preserved. Marcic v Thames Water Utilities Ltd [2003] UKHL 66 illustrated the opposite case, where the statutory duty was essential to the nuisance claim.
2. Misleading a regulator is not a discrete head of abuse. The conduct must amount to abuse of a dominant position capable of affecting trade. AstraZeneca v Commission, in both the General Court and CJEU judgments, required a fact-specific and contextual assessment of misleading representations to public authorities.
3. On the pleaded case, Ofwat relied on the accuracy and completeness of pollution information because the water companies were legally required to provide it for price-control reviews. The alleged misleading conduct therefore depended on breach of the reporting conditions. The reporting breach was fundamental, not merely an underlying cause or background fact. The claim could not be maintained as a free-standing abuse claim.
4. The statutory scheme had to be considered realistically and purposively. The price-control regime both facilitated the statutory monopolies and protected consumers from excessive charging. The loss alleged resulted from the reporting breach causing Ofwat to set higher revenue allowances, even though Ofwat’s subsequent application of the regime was not itself a breach. Information supplied to the Environment Agency could not independently affect trade; its pleaded relevance was its onward effect on Ofwat.
5. The Tribunal’s emphasis on causation and loss was not the best formulation, but its conclusion was correct. The claims were excluded by section 18(8). Zacaroli LJ considered that the core ingredients were inaccurate information, its causative effect on revenue allowances and charges, and consumer harm. In his view, the fact that the information also breached a licence condition was not essential, and the appeal should have been allowed.

1. Court of Appeal (Civil Division): appeal dismissed by the majority in [2026] EWCA Civ 222; Zacaroli LJ dissented.
2. Competition Appeal Tribunal: refused a Collective Proceedings Order on the basis that the claims were excluded by section 18(8) of the Water Industry Act 1991, in [2025] CAT 17.