The UK Government has today announced a consultation on proposed amendments to the National Security and Investment Act 2021 (Notifiable Acquisitions) (Specification of Qualifying Entities) Regulations 2021 (the NARs). The NARs contain details of the 17 sensitive sectors where mandatory NSIA filings are required for certain changes of control. Any changes to the scope of these sectors will therefore have an impact on when a mandatory filing needs to be made, with immediate consequences for deal timing and – in some cases – deliverability.
The previous Government issued a Call for Evidence on the NSIA in November 2023, responses to which highlighted a number of areas in which the regime could be improved. The present Government also issued a report on the NARs published in December 2024. Following these publications, the Government's Industrial Strategy Paper published in June 2025 confirmed its intention to consult on changes to the NARs, as has been announced today. The consultation period opens today, and will close on 14 October 2025.
In its introduction to the consultation, the Government stresses that its intention remains to ensure that the NSIA regime captures sensitive national security risks, and that most transactions should be unaffected by it. Overall, the Government estimates that the changes may reduce the number of mandatory filings by up to 10 per year, but that they may increase that number by up to 35.
New activities brought within the mandatory notification regime
The Government proposes to add a new sector defining activities in the water sector that will become subject to the mandatory notification regime. The consultation notes that "The UK's critical national water infrastructure is facing increasing risks to its resilience in a growing threat landscape", and that allowing malicious actors through investment to obtain the ability to threaten this infrastructure represents "a variety of national security risks".
Under the proposals, all 17 of the appointed water and sewerage companies and water-only companies would be within the scope of the mandatory filing regime. Companies operating solely as retailers in the non-household retail market would not be affected.
Reorganisation of existing mandatory notification sectors
In order to provide better clarity, the Government proposes to take out parts of the existing "Advanced Materials" sector to create new standalone sectors for (i) Semiconductors, and (ii) Critical Minerals.
The new "Semiconductors" definition will also include Computing Hardware (which currently has its own standalone sector), and the definition of these sectors will updated to include some additional activities.
For Critical Minerals, the Government proposes to "harmonise" the critical minerals list with the Critical Mineral Intelligence Centre's criticality assessments, but this sector will continue to cover additional strategically important minerals used in defence and scientific applications. Extraction, processing and recycling will be added to the list of relevant activities in this sector.
Updates to other existing sectors
In relation to the other existing sensitive sectors, the Government proposes a number of changes that it explains are intended to ensure that those definitions remain up-to-date.
Changes are proposed to "loosen the scope" of the regime in cases where the Government considers the national security risk to be low. These include Artificial Intelligence (to exclude the use of "off the shelf" AI for internal processes, but adding in certain categories of AI development) and Energy sectors (amendments to the definition of "aggregators", new cumulative capacity thresholds, and the addition of multi-purpose interconnectors).
Conversely, changes are proposed in the sectors for "Critical Suppliers to the Government" and "Suppliers to the Emergency Services", to reflect changes to the risks identified in those sectors. In Critical Suppliers to the Government, this includes narrowing the definition of relevant public sector authorities, and replacing "List X accreditation" with "Facility Security Clearance". For Suppliers to the Emergency Services, the sector will be amended to bring certain subcontractors within the scope of the regime.
Other changes are proposed in the sectors defining Communications, Data Infrastructure, and Synthetic Biology.
No effect on the types of transaction affected
The scope of the consultation is limited to addressing the sectors of the economy to which the mandatory notification regime applies. It does not touch on other key factors determining whether a filing is required. The Government is however looking at other ways to reduce the burden on businesses, including in relation to mandatory notifications for certain internal reorganisations and the appointment of liquidators.
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