Carbon Six Engineering Limited v The Commissioners for HMRC

Decision date: 29 January 2026

Neutral citation: [2026] UKFTT 177 (TC)

Overall AI summary confidence: high

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Short overview

This short overview is intended to summarise the case, issues and outcome so far as they are supported by the judgment.

AI confidence in this short overview: high

This case concerns HMRC's application to set aside a barring order entered under rule 8(1) after HMRC failed to comply with an unless order requiring service of a statement of case and responses. The Tribunal refused HMRC's application, finding the breach serious and the explanations (internal handover/administration error) not good reasons to lift the bar, and exercised rule 8(8) to summarily allow Carbon Six's appeal because no statement of case had been served. Costs procedure and time limits were specified for the appellant to pursue costs.

Ratio decidendi

This summary is intended to identify the ratio decidendi, meaning the legal reasons for deciding and the binding part of the decision.

AI confidence in this ratio decidendi summary: high

Where a party breaches an unless order the three-stage Denton/Martland relief-from-sanctions test applies, and the Tribunal must give particular weight to compliance with its directions and the need for efficient conduct of litigation; routine administrative explanations (such as inbox handover errors) may be insufficient to outweigh the need to enforce unless orders, especially where there is a history of repeated non‑compliance.

Obiter dicta

This summary is intended to identify obiter dicta, meaning observations made by the way that were not necessary to deciding the case and are not binding.

AI confidence in this obiter dicta summary: medium

The Tribunal indicated that the fact an appeal is part of a larger group of related appeals will not, absent exceptional circumstances, justify lifting a barring order caused by non‑compliance, and that public bodies are expected to maintain effective internal arrangements to ensure Tribunal communications are actioned; public‑duty arguments do not excuse procedural default.