I INTRODUCTION

1 January 2026 marks the pivotal date for what Treasurer Chalmers, in his second reading for the Treasury Laws Amendment (Mergers and Acquisitions Reform) Bill 2024 (Cth), has dubbed ‘the biggest reforms to Australia's merger settings in almost 50 years’.[1] Targeting anti-competitive mergers and acquisitions the Treasury Laws Amendment (Mergers and Acquisitions Reform) Act 2024 (Cth) (‘Acquisition Amendments’) has amended the Competition and Consumer Act 2010 (Cth) (‘CCA’) to introduce a formal regime contingent upon compulsory notification—previously Australia was ‘one of only three OECD countries’ lacking compulsory notification.[2] The object of the CCA is ‘to enhance the welfare of Australians through the promotion of competition and fair trading and provision for consumer protection’.[3]

Below is an overview and analysis of the changes centering especially on emerging obligations, contentious suspensory provisions, as well as the circumstances and classes requiring notification—including exceptions.

II THE LEGISLATION

This new regime derives principally from two sources. First is the Acquisition Amendments, and second is the Competition and Consumer (Notification of Acquisitions) Determination 2025 (‘The Determination’) (Cth) which, as delegated legislation, contains substantial components of reform viz. fees, exceptions, and circumstances of mergers and acquisitions subjected to compulsory notification.[4] The Determination too was amended by the Competition and Consumer (Notification of Acquisitions) Amendment (2025 Measures No. 1) Determination 2025 (Cth).[5]

III CONTEXT—THE OLD SYSTEM

Previously, Australia implemented an informal review system for mergers and acquisition. Section 50 of the CCAinstituted a prohibition on directly or indirectly acquiring shares of potential market competitors, following a test—from sub-ss (1)–(3)— of whether an acquisition had the effect of ‘substantially lessening competition in any market’.[6]However, companies could seek legal protection for acquisitions through ‘authorisation’, under s 88(1), which would result in restrictive trade provisions not applying to the applicant, other persons named in the acquisition, and other specified parties.[7] Nevertheless, the ACCC could not authorise acquisitions that, under s 90(7), would be ‘substantially lessening’ of ‘competition in any market’; failed to produce a public benefit that would outweigh the detriment to the public; or did not assist in response to or recovery from national emergency—this too was subjected to public benefit analysis.[8]

Though this authorisation system may benefit the legal system and commerce to an extent, particularly by reducing friction for pro-competitive mergers, ultimately its reactive nature was not conducive to the object of promoting competition.[9] The final impact analysis for the new regime even noted that under the old system ‘at least one meaningful merger each year … [was] not notified’ noting that ‘the number of mergers not notified [was at the time] unknown’ and that ‘this number could be higher.’[10]

Nevertheless, the old system has been entirely abrogated. Its remnants persist, though, with depleted relevance and notable substitutions, as the new regime supplants it.[11]

IV THE NEW REGIME

In contrast, the new regime subjects acquisitions to a potential multi-phased review process before permitting acquisition. The process for determining an acquisition is divided into phase 1, phase 2, and a public benefit application. During phase 1 the ACCC evaluates a notification and, under s 51ABZE(1) paras (a)–(b), the Commission may make a determination that the acquisition either ‘may’ be or ‘must not be put into effect’ with possible conditions or anti-good-will stipulations imposed reflecting ss 51ABZF–G.[12] This is excellent for promptly deciding unambiguous notifications, however, in phase 1 the ACCC may opt to commence a phase 2 review instead. Unfortunately for eager acquirers, phase 2 reviews, under s 51ABZJ(1) paras (a)–(b), will typically extend the process, but are required for undetermined acquisitions that ‘could in all circumstances’ have or likely have the effect of ‘substantially lessening competition in any market’ (‘SLC test’.) The standard of the SLC test is established by s 51ABZH(4) which is drafted to protect consumers from acquisitions with the effect of ‘creating, strengthening or entrenching a substantial degree of power in the market.’ That said, once the phase 2 review is complete a determination—under s 51ABZE(1)—can be made.[13]

However, should a phase 1 determination prove unfavourable, a principal party can pursue a public benefit application—within 21 days of the failed determination under s 51ABZP(2)(a).[14] The result of this application is a determination on whether the acquisition is ‘of public benefit’, with the legislation permitting such beneficial acquisitions—s 51ABZW(1)(a)–(b).[15] This determination will only occur if the Commission is satisfied that ‘the acquisition would, in all the circumstances, result, or be likely to result, in a benefit to the public’ and ‘the benefit would, in all the circumstances, outweigh the detriment to the public that would result, or be likely to result, from the acquisition’. The ACCC must also regard the object (s 2) of the CCA and ‘all relevant matters’ (under s 51ABZW(2)–(3)).[16] The standards set regarding public benefit applications, for both the application itself and the Commission, are drafted to be onerous as the legislation exchanges some efficiency for consumer protection. Ergo, compared to the informal system, the new regime better suits the object of the CCA, though there are concerns over the number of acquisitions that the ACCC must consider which is estimated to more than quadruple.[17]

Even still, acquisitions can be expedited as waiver is possible under s 51ABU(1). This benefits  non-contentious acquisitions especially, and enables a person to apply to the ACCC for a determination that an acquisition is not required to be notified.[18] Consequently this waiver can prevent systematic gridlock and assure principal parties that they are not defaulting on their newfound obligations or can confirm that they must notify. This is beneficial as defaults may result in resource draining litigation.

V NEW OBLIGATIONS

Section 45AW introduces the novel obligation to notify the ACCC of particular acquisitions.[19] 

Though this obligation only applies to certain acquisitions. This legislation specifies applicable circumstances through s 51ABP(1), and specific classes of acquisition through s 51ABQ(1)— which both interact with on The Determinations.[20] In outlining general circumstances the new regime encapsulates a greater variety of transactions and acquisitions meaning the new has the potential to promote competition in the long-term. Conversely, the class-based approach directly targets specific acquisitions to mollify particular types of anti-competitive acquisitions. A significant benefit of this system is that the classes, thresholds, and exemptions can be altered by iterative legislation. The tiered system of monetary tests also efficiently interacts with the circumstances of acquisition to clarify which actually acquisitions require notification.

VI ENSURING COMPLIANCE

Further, defaulting on this obligation amounts to contravention of s 45AW, and may occur in the three scenarios under s 45AW(d) sub-paras (i–iii). First (s 45AW(d)(i)) is if the acquisition is not a notified acquisition when the acquisition comes into effect; second (s 45AW(d)(i)) is if the acquisition comes into effect when no notice of the acquisition bears ‘an effective notification date’; and third (s 45AW(d)(iii)) is if the effective notification date is ‘stale’. These provisions interact with a number of separate sections also introduced by the amendment to fortify the new regime, and minimise circumvention.[21] Of note are ss 51ABG and 51ABZ. Section 51ABG outlines when notifications become stale—which is 12 months after the time the Commission makes a determination under ss 51ABZE(1)(a) or 51ABZW(1)(a).[22]Though this may result in a higher volume of applications to be processed, as stale notifications cannot be relied upon, this provision ensures that the ACCC only approves acquisitions with recent information which also will likely prevent unnecessary litigation. Section 51ABZ also interacts with s 51ABY to prevent the commission from considering notifications that are ‘materially incomplete or misleading’, this is an instance of legislative diligence with similar sections existing for public benefit applications, and material changes of fact.[23] By establishing a standard of notifications at the level of material information, the amendments allow the process to be thorough, and consistent which can be beneficial to all relevant parties. Further, the transparency of the new regime can be especially beneficial to those preparing notifications as s 51ABZ(1)(b) requires the ACCC to provide written notice of grounds of rejection under s 51ABY(1).[24] Transparency is also provided through the public register, and the onus on the ACCC to provide notice to principal parties upon commencing different phases of review inter alia. However, not all aspects of the regime are commercially beneficial.

VII AUTOMATIC VOIDING

Automatic voiding is a suspensory mechanism and the subject of intricate criticism which has been acknowledged, and may result in amendments following March 2026 at the earliest. This severe provision, unlike s 45AW, not only prohibits unnotified acquisitions, but actively voids unapproved acquisitions—and potentially carries undesirable implications for contracts regarding acquisition.[25] ‘Stayed’ is the relevant designation under s 51ABE and occurs if an acquisition is required to be notified, and has failed that requirement; if the most recent notification of the acquisition has not been ‘finally considered’; if the most recent s 51ABZE(1) determination is that the acquisition ‘must not be put into effect’; among other issues.[26] Nevertheless, this provision is ostensibly concerned with consumer protection and is rationally consistent with the objects of the CCA. Though for critics this mechanism may benefit from being redrafted or repealed as it can prove economically counterproductive. Amendment  can particularly serve pro-competitive mergers which may challenge existing market dominance. The fees and penalties of the new regime also disincentivise even pro-competitive acquisitions meaning the new legislation risks double-penalising even pro-competitive mergers contrary to the objects.[27]

VIII CIRCUMSTANCES

The circumstances outlined by The Determination only require notification past certain thresholds. For instance, the acquisitions of the ‘large or larger corporate groups’ circumstance require notification past tier-1 of the acquired shares or assets revenue test (≥$50 million) or tier-1 of the transaction value test (≥$250 million.) [28]

The inclusion of creeping or serial acquisitions, and certain asset acquisitions within the ‘General Circumstances’ division is an attempt to comprehensively protect consumers and demonstrates that the scope of the new regime extends past simple transactions into calculated and consistent anti-competative behaviour.[29]

IX EXCEPTIONS TO NOTIFICATION REQUIREMENTS:

In addition to the circumstances above, exceptions exist to mitigate undesirable microeconomic consequences from the new regime and prevent disruption to key industries especially in the tertiary sector—namely financial institutions, and superannuation entities. Also notable are the  exceptions relating to land, including land acquisitions ‘undertaken in the ordinary course of business’ and land for the purpose of ‘developing residential premises’. These exceptions reflect contemplation into the sectors affected by the new regime including the supply-side issues of residential premises—although this is the product of iteration and was not initially the case.[30] Even if the residential premises exception proves ambivalent for the typical consumer, which is likely considering the general trends of that sector, the clarity provided is pragmatic and might prevent unnecessary legal disputes in the future.

XI CLASSES

The Determination can also target entities under pt 3 by specifying that ‘classes’ of acquisition require notification. Prominently, the current legislation hinders major supermarket acquisitions directly. This targets the duopoly established by the major supermarkets (Coles Group Limited (ABN 11 004 089 936); Woolworths Group Limited (ABN 88 000 014 675) and each of their connected entities) which bears notable market dominance.[31] Nevertheless, it remains to be determined whether the 5-year sunset clause allows sufficient time to promote competition or if any unintended consequences may emerge from these provisions and the regime as a whole.[32]

XII THE AMENDMENTS AS A WHOLE

Regarding the object of the CCA, this new regime is capable of promoting competition especially in the long-term. However, the effects to the consumer may prove both profound and subtle as the regime is essentially preventative, meaning it disrupts market entrenchment rather than reversing current monopolies, oligopolies etc.[33] Generally, amendments to this new regime must be erudite to avoid hindering ordinary business operations, or pro-competitive acquisitions as that would restrain rather than promote competition. Though, for protecting fair trade, consumers, and competition itself, this regime is a net benefit if not a necessity, and is an improvement over its predecessor.

XIII FOOTNOTES

[1]Treasury Laws Amendment (Mergers and Acquisitions Reform) Bill 2024 (Cth); Commonwealth, Parliamentary Debates, House of Representatives, 10 October 2024, 1[4] (Jim Chalmers, Treasurer) <https://parlinfo.aph.gov.au/parlInfo/search/display/display.w3p;query=Id%3A%22chamber%2Fhansardr%2F28036%2F0011%22>.

[2] Treasury Laws Amendment (Mergers and Acquisitions Reform) Act 2024 (‘Acquisition Amendments’); Competition and Consumer Act 2010 (Cth) (‘CCA’); Ibid [10]–[13].

[3] CCA (n 2) s 2.

[4] Acquisition Amendments (n 2); (Notification of Acquisitions) Determination 2025 (Cth)  (‘The Determination’).

[5] Competition and Consumer (Notification of Acquisitions) Amendment (2025 Measures No. 1) Determination 2025 (Cth).

[6] CCA (n 2) s 50(1).

[7]CCA (n 2) s 88(1)–(2).

[8]CCA (n 2) s 2.

[9]CCA (n 2) s 50(3) as amended by Acquisitions Amendments (n 2).

[10] Impact Analysis Merger Reform: A Faster, Stronger and Simpler System for a More Competitive Economy (Final Report, September 2024) 26.

[11] See generally CCA (n 2) s 50(3). Note that s 50(3) of the CCA (n2) is an instance of a substitution implemented for the purposes of consistency with the tests of the new regime. To understand further see Explanatory Memorandum, Treasury Laws Amendment (Mergers and Acquisitions Reform) Bill 2024 (Cth) 51[4.20]–52[4.30].

[12] CCA (n 2) ss 51ABZE(1)(a)–(b).

[13] Ibid ss 51ABZF–G, 51ABZH(4), 51ABZE, 51ABZM.

[14] Ibid s 51ABZP(2)(a).

[15] Ibid s 51ABZW(1)(a)–(b).

[16] Ibid ss 51ABZW(2)–(3).

[17] Impact Analysis Merger Reform: A Faster, Stronger and Simpler System for a More Competitive Economy (Final Report, September 2024) 26.

[18] See generally CCA (n 2) s 51ABU.

[19] Ibid s 45AW.

[20] Ibid ss 51ABP(1), 51ABQ(1). See generally The Determinations (n 2) pts 1–3.

[21] Ibid s 45AWd(i)–(iii).

[22] Ibid ss 51ABG, 51ABZ, 51ABZE(1)(a), 51ABZW(1)(a).

[23] CCA (n 2) ss 51 ABY, 51ABZ.

[24] Ibid s 51ABY, 51ABZ(1)(b).

[25] For the identification of automatic voiding and other issues see Jacqueline Downes, Felicity McMahon and Roy Chowdhury, ‘Merger Reforms: A Mandatory and Suspensory Merger Regime with the ACCC as Decision Maker’, Insight (Web Page, 23 December 2025) [12]. <https://www.allens.com.au/insights-news/insights/2025/12/merger-reforms-a-mandatory-and-suspensory-merger-regime-with-the-ACCC-as-decision-maker/#anchor7>.

[26] CCA (n 2) ss 51ABE, 51ABF, 51ABZE(1), 51ABZW(1)(a).

[27] CCA (n 2) s 2.

[28] The Determination (n 2) pt 2 div 1 sub-div 2–1, pt 1 sub-divs 1–10, 1–12.

[29]Ibid.

[30] See generally The Determination (n 2) pt 2 div 2. See also, Jacqueline Downes et al., ‘Merger reform legislation: complex process risks capturing more transactions than intended’, Insight (Web Page, 11 October 2024) [6] <https://www.allens.com.au/insights-news/insights/2024/10/merger-reform-legislation-complex-process-risks-capturing-more-transactions-than-intended/#anchor1>. This article was written at a time before the inclusion of land for residential premises as an exception.

[31] Ibid pt 3 div 1.

[32] Ibid sub-div 3–4.

[33] CCA (n 2) s 2.