United Kingdom: security screening and the CMA
Buying more than 25% of a company active in one of 17 sensitive areas, such as defence, energy or data infrastructure, must be approved by the government before it completes. In the year to March 2026 the government reviewed 1,220 notified deals and called in 60 for a closer look. Changes to the list of areas have been announced but are not yet in force.
The Competition and Markets Authority can review a merger when the business being bought has UK turnover above £100 million, or when the combined business would supply 25% or more of something in the UK. Deals where no party has UK turnover above £10 million fall outside its reach.
Source: NSI Act annual report 2025-26 · CMA jurisdiction guidance
European Union: Brussels for the largest deals, national screening for the rest
Only very large mergers go to the European Commission: combined worldwide turnover above €5 billion and more than €250 million in the EU for each of at least two of the companies, or a lower alternative test across three member states. Most owner-operated acquisitions fall far below that.
Foreign investment is screened country by country. A new EU regulation adopted in June 2026 requires every member state to run a screening system, and national rules can apply whatever the size of the deal. Each member state has the last word on deals in its territory.
Source: European Commission, merger procedures · European Commission, investment screening
Gulf: full foreign ownership in the UAE, merger filing in Saudi Arabia
Since 2021, foreign investors can own 100% of a mainland company in the United Arab Emirates, except in activities of strategic impact, such as defence, banking and telecommunications, where ownership can be limited.
In Saudi Arabia a deal must be notified to the General Authority for Competition, and cleared before it closes, when the parties’ combined worldwide sales exceed SAR 200 million and the further sales tests set by the Authority are met.
Source: UAE Government portal · Chambers, Merger Control 2026: Saudi Arabia
Australia: merger filing is now mandatory
Since 1 January 2026, acquisitions that meet the thresholds must be notified to the Australian Competition and Consumer Commission and cleared before they complete. The main test is combined Australian revenue of A$200 million or more, with a target earning A$50 million or more in Australia or a deal worth A$250 million or more.
Foreign investment review is separate. A private buyer from a listed free-trade partner, including the U.S., Canada and the UK, needs approval to buy 20% or more of a non-sensitive Australian business only above A$1,498 million in 2026. Sensitive and national-security businesses have lower thresholds.
Source: Notification of Acquisitions Determination 2025 · Foreign Investment Review Board, 2026 thresholds
India and Singapore
Since 10 September 2024, a deal worth more than INR 2,000 crore needs prior approval from the Competition Commission of India when the target has substantial business operations in India, even if the target is otherwise small.
In Singapore, notifying a merger to the competition regulator is voluntary. A separate law, the Significant Investments Review Act 2024, applies only to a short list of designated entities.
Source: Competition Commission of India · Competition and Consumer Commission of Singapore · Office of Significant Investments Review
Africa: new South African thresholds
From 1 May 2026, a merger in South Africa must be notified before it is put into effect when the parties’ combined South African turnover or assets reach R1 billion and the target’s reach R200 million. Above R9.5 billion combined and R280 million for the target it is a large merger. Smaller deals can still be called in.
Across the COMESA common market in eastern and southern Africa, a merger must be notified when the parties’ combined turnover or assets in the region reach COM$60 million and at least two of them reach COM$10 million each.
Source: Competition Commission South Africa · COMESA Competition and Consumer Protection Rules 2025
General information, not legal, tax or investment advice. Thresholds and rules change; confirm them with a qualified adviser in the relevant jurisdiction. Sources checked 2 November 2026. GLZR handles sourcing, initial qualification and introductions. It does not provide a formal valuation, financing approval or underwriting.