UK NS&I regime

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This Overview guides you to our materials on the UK National Security and Investment (NSI) regime, with links to legislation, guidance, practice notes and transaction tools.

The NSI Act 2021 creates a standalone screening regime for acquisitions that may pose national security risks, operating alongside but separately from UK merger control. Administered by the Investment Security Unit on behalf of the Secretary of State, it applies to qualifying entities and assets in or connected to the UK, including extraterritorial transactions.

Practitioners should understand when mandatory notification applies in specified sensitive sectors, the control thresholds (25%, 50% and 75% shareholdings and certain voting rights) and the separate concept of material influence, plus what constitutes a trigger event. Non - notified deals can be called in, including those completed since 12 November 2020. Completing a notifiable acquisition without clearance is void and may attract civil and criminal sanctions, including significant fines.

The statutory timetable comprises a 30 working day review, followed - if called in - by an assessment period of 30 working days, extendable by 45 working days. Outcomes range from unconditional clearance to final orders imposing conditions, prohibiting...

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