Navigating Australia’s new mandatory merger control regime

The Foreign Investment Review Board (FIRB) also upgraded its online portal on 17 January 2026 to reflect how these new ACCC merger control requirements will interact with the foreign investment framework and streamline how competition issues are assessed across both regimes.

Although the foreign investment framework is independent of the ACCC’s merger control regime, competition remains an integral element of the national interest test under the Foreign Acquisitions and Takeovers Act 1975.

In late November 2024, the Australian parliament passed the Treasury Laws Amendment (Mergers and Acquisitions Reform) Bill 2024. The ACCC described the passage of the bill as “the most significant change to Australia’s merger regime” in the last 50 years, replacing the previous voluntary merger regime.

Under the previous voluntary notification regime, merger parties were only recommended to notify the ACCC to obtain advice that the acquisition will not contravene Australia’s merger laws.  It is now mandatory to notify the ACCC of transactions that meet specified thresholds, which are based on parties’ revenue, transaction values, control and, in some cases, whether the transaction is captured by a ‘class determination’. Class determinations require certain types of transactions, such as supermarket land acquisitions, to be notified to the ACCC for merger review even if they do not meet the general notification thresholds.

Acquisitions of shares and assets of a business may fall within the scope of the new regime, subject to the relevant monetary threshold being triggered. Assets are broadly defined as including both legal and equitable interests in tangible and intangible assets, subject to certain qualifications. An acquisition would need to be notified if the target business carries on business in Australia, and the transaction results in the acquirer or its subsidiaries gaining ‘control’ of the target or increasing its voting power in the target beyond certain thresholds.

Although the new merger control regime commenced fully on 1 January 2026, several amendments to the new rules were announced in December 2025 and will apply from 1 April 2026.

The mandatory merger notification thresholds are:

Large acquirer

If the Australian revenue of the combined businesses, including connected entities, is A$200 million or more; and:

• in a share acquisition, the target business has Australian revenue of A$50 million or more;
• in an asset acquisition, where all or substantially all of the business’s assets are being acquired, the Australian revenue attributable to the assets is at least A$50 million;
• the global transaction value is A$250 million or more; or
• from 1 April 2026, where an asset acquisition does not involve all or substantially all assets of a business, the global transaction value is at least A$200 million.

Very large acquirer 

If a ‘very large’ business, has Australian revenue of A$500 million or more including connected entities, and:

• in a share acquisition, the target business has Australian revenue of at least A$10 million; or
• in an asset acquisition, where all or substantially all of the business’s assets are being acquired, the Australian revenue attributable to the assets is at least A$10 million; or
• from 1 April 2026, where an asset acquisition does not involve all or substantially all assets of a business, the global transaction value is at least A$50 million.

Serial or ‘creeping’ acquirer

Intended to allow the ACCC to scrutinise the cumulative competitive effect of serial acquisitions over the preceding three-years. An M&A transaction must be notified, subject to certain exclusions, if one of two different monetary thresholds are met:

• where the combined Australian revenue of the merger parties is at least A$200 million and the cumulative Australian revenue from acquisitions in the same or substitutable goods or services in the prior three years is at least A$50 million; or
• where the acquirer group’s Australian revenue is at least A$500 million and the cumulative Australian revenue from acquisitions in the same or substitutable goods or services in the prior three years is at least A$10 million.

From 1 April 2026, transactions that do not involve acquiring control over a business may nonetheless be notifiable if one of the ‘large acquirer’ or ‘very large acquirer’ monetary thresholds is met and the acquirer’s voting power in the target business increases above 20%, depending on the target company type, either listed or unlisted, and the acquirer’s preexisting shareholding in the target.

The merger notification requirements are subject to exemptions, including in relation to certain land acquisitions and certain types of financial markets transactions.

The applicable substantive competition law test – whether the transaction would substantially lessen competition in a market in Australia – remains largely the same as the old regime, but this concept has been expanded to include whether a transaction has the effect or likely effect of creating, entrenching or strengthening a position of market power, which is directed at regulating acquisitions by entities that are already in positions of market power in Australia.

Interaction with FIRB framework

Since the introduction of the mandatory notification regime on 1 January, the foreign investment portal has been updated to account for the mandatory notification to ACCC. The updates include:

• foreign investors must indicate whether their acquisition will be notified to the ACCC;
• Treasury may refer acquisitions involving foreign investors that are not required to be notified under the merger control regime to the ACCC for a competition assessment. If either Treasury or the ACCC identifies potential competition issues, the two will consult to make a further assessment; and
• for acquisitions involving foreign investors that are required to be notified under the merger control regime, or which have chosen to voluntarily notify the ACCC of an acquisition below the notification threshold, a decision by the ACCC is required for the finalisation of the competition aspect of the assessment under the foreign investment framework.

FIRB’s upgrades to its portal are aimed at improving functionality and incorporate changes required under the mandatory merger control regime, while minimising the burden on applicants by tailoring questions to the ACCC notification status of the transaction.  
Where parties are required to notify the ACCC or have been granted a notification waiver, they will be able to supply an ACCC notification or waiver reference number and will not been required to provide competition-related information to Treasury, as this will be assessed by the ACCC.

The same requirement is in place where a party has not been notified and has instead voluntarily notified to the ACCC.

Where a merger or acquisition is not required to be notified to the ACCC and the parties have not voluntarily notified, they may be asked to provide a base level of information relating to competition when using the portal because these acquisitions are subject to section 50 the Competition and Consumer Act 2010, which prohibits acquisitions which would directly or indirectly result in a substantial lessening of competition. Factors which may be taken into account when determining this include level of concentration in the market; substitutes available; and growth and innovation in the market.

Considerations for foreign investors

Previously, foreign investors were put at a disadvantage in Australia in competitive auction processes, as they may have required foreign investment (FIRB) approval to acquire Australian assets. Accordingly, the regulatory and timetable risk for sellers in selecting a foreign bidder in a competitive auction process could lead them to favour local Australian bidders, even if the offered purchase price is lower. The new merger control regime will mean that both Australian and foreign bidders may, for larger transactions, be subject to regulatory and timetable hurdles via the new ACCC merger filing process, as well as, for foreign bidders, the FIRB approval process. This will put foreign bidders on a more even footing against their Australian competitors in competitive auction processes.

The new regime aligns Australian law more closely with the mandatory and suspensory merger control regimes present in many overseas jurisdictions, such as the EU-level merger control regime and the national merger control rules of various EU countries, which have had mandatory filing requirements for many years.

Co-written by Nithini Perera of Pinsent Masons.