Gardner Aerospace v Upton: High Court refuses disclosure of national security assessments

The High Court has refused to order disclosure of government national security assessments in a commercial dispute between Gardner Aerospace Holdings Limited and its former director, despite acknowledging the documents' relevance to causation issues at the heart of the claim.

Mr Justice Richard Smith delivered his judgement on 17 October 2025, dismissing the aerospace companies' application for third party disclosure of sensitive government materials whilst granting access to less controversial communications.

The underlying dispute

Gardner Aerospace Holdings Limited (GAH) and Gardner Group Limited brought proceedings against their former CFO and interim CEO, Antony Upton, alleging he breached his duties by lobbying against a refinancing transaction involving Chinese entities. The claimants contend that Upton's conduct influenced the UK Government's decision to issue a call-in notice and Final Order under the National Security and Investment Act 2021, causing approximately £7 million in losses through delayed funding and additional costs.

The transaction involved Sichuan Development Holding Company Limited (SDH), a Chinese state-owned fund, increasing its shareholding in Ligeance Aerospace Technology Company Limited (LAT), which owned Gardner. The Secretary of State ultimately imposed conditions on the transaction in October 2022, including the appointment of a government observer to GAH's board and restrictions on information sharing with Chinese entities.

The disclosure application

The claimants sought four categories of documents from the Department for Business and Trade, Cabinet Office (Investment Security Unit), and Ministry of Defence. These included meeting records and emails between Upton and government officials, assessments prepared for the Secretary of State's decision-making, and correspondence between MPs and government departments.

Whilst the government adopted a neutral stance on disclosing meeting records and MP correspondence (Categories 1 and 4), it strongly resisted disclosure of the national security assessments (Category 3). The Permanent Secretary to the Cabinet Office submitted a Public Interest Immunity Certificate stating that disclosure would pose "a real risk of causing serious harm to the UK's national security" and international relations.

Balancing competing interests

The court recognised the inherent tension between facilitating fair resolution of private disputes and protecting national security. Mr Justice Smith accepted that the assessment documents would satisfy the relevance and necessity requirements under CPR Part 31.17, as they could illuminate the causation issue central to the dispute.

However, the judge ultimately deferred to the government's assessment of sensitivity. He acknowledged that documents analysing specific transactions for national security purposes reveal not merely transaction-specific information but also the government's processes, methodology and decision-making approach in this sensitive area.

The court rejected the claimants' proposal for partial disclosure with redactions or gist statements. Given that the substantial majority of responsive documents had been redacted for sensitivity reasons, and that the most relevant portions concerning the impact of Upton's representations were among the redacted material, partial disclosure would not meaningfully assist the fair disposal of the claim and might create unfairness.

The judgement reinforces the exceptional nature of third party disclosure applications, particularly where national security considerations arise. Whilst acknowledging the challenges this poses for litigants seeking to establish causation in cases involving government decision-making, the court maintained that protection of the public interest must take precedence where genuine national security concerns exist.