What changed and why it matters now?
From the start of 2026, Australia’s merger control framework has moved from a largely voluntary engagement model to a mandatory, suspensory system for acquisitions that meet prescribed thresholds. Parties now must notify and wait for clearance (or a waiver) before implementing the transaction.
This is not a mere procedural refresh; it is a structural reallocation of transaction risk. The new regime is designed as a mandatory administrative approval system, implemented through the legislative reforms enacted via Treasury Laws Amendment (Mergers and Acquisitions Reform) Act 2024, with core aspects commencing at the beginning of 2026 and additional refinements commencing shortly thereafter.
The “mandatory and suspensory” label is only the headline. The deeper operational shift is that merger control is now a gating item that can dictate signing mechanics, long‑stop settings, public deal sequencing, and for international dealmakers, the ability to align Australia’s new clock with overseas merger and foreign investment timelines.
The notification net: thresholds, nexus, and the serial acquisitions lens
Australia’s mandatory notification obligation is triggered by a set of monetary thresholds based on Australian revenue and/or global transaction value, with the thresholds set in legal rules made by a Treasury Minister.
At a practical level, Australian law practitioners (and foreign deal teams) should internalize three features of the threshold design.
First, the headline “large merged firm” and “very large acquirer” tests are broad and revenue-led:
- Large merged firm threshold: notification is required where the combined Australian revenue of the merger parties is at least A$200 million, and either the target’s Australian revenue is at least A$50 million or the global transaction value is at least A$250 million.
- Very large acquirer threshold: notification is required where the acquirer group’s Australian revenue is at least A$500 million and the target’s Australian revenue is at least A$10 million.
Second, the regime is expressly designed to capture “creeping” or “serial” acquisitions through a lookback lens. Where the relevant size threshold is met, prior acquisitions over the past three years involving predominantly the same or substitutable goods or services can be accumulated toward a cumulative revenue threshold (A$50 million for large merged firm cases; A$10 million for very large acquirers), subject to stated exclusions.
Third, the notification obligation turns on a local nexus and the presence (or absence) of exemptions. As the ACCC explains, even where a monetary threshold is met, notification is only required where the target is “connected with Australia” (carrying on business in Australia) and no exemption applies.
Two further changes are particularly relevant given the calendar: the Government deferred some new “control” and “asset” threshold measures to commence on 1 April, 2026, explicitly to provide businesses more time to prepare. These include (among other things) additional asset thresholds for acquisitions of assets that are not “all or substantially all” of a business (with separate tests for acquirer groups at A$200 million and A$500 million Australian revenue) and new voting power thresholds that can require notification in specified shareholding step‑ups.
Finally, Australia’s system also contemplates targeted notification requirements for defined “high‑risk” acquisitions. The ACCC notes that a Treasury Minister may set additional notification requirements, and the published thresholds include targeted obligations for specific acquirers (for example, certain acquisitions by major supermarkets irrespective of general thresholds).
Foreign bidders and regulatory stacking in public deals
Any analysis of Australia’s new merger regime in isolation risks missing the commercial driver: the Australian public M&A market is inherently cross‑border.
In its 2026 edition of the public M&A deal report, Ashurst reports that 40 binding public M&A deals above A$50 million were announced in 2025, and that foreign bidder involvement increased: 25 of those 40 deals involved a foreign bidder. That statistic is not just market color. It signals that a significant part of Australia’s deal pipeline will be run by sponsors and strategics whose internal processes, bidder timetables, and disclosure norms are shaped by non‑Australian merger regimes.
Regulatory “stacking” compounds this dynamic. Many inbound transactions also require foreign investment screening, in addition to competition clearance. For example, Australia’s foreign investment guidance notes that investors may need to submit an investment proposal for review if proposing to acquire a “substantial interest” (generally at least 20%) in a general Australian business, corporation, or trust, subject to thresholds.
This is a key practical point for deal lawyers: Australia’s new ACCC gating (with defined clocks and fees) will often run in parallel with a separate screening track administered through Foreign Investment Review Board processes and policy.
The immediate consequence for Australian law firms is that “domestic counsel” is never only domestic counsel in a cross‑border public deal. A bidder headquartered offshore will expect Australian counsel to anticipate, calendar, and coordinate the global regulatory choreography, even where the legal work product must be delivered locally in each jurisdiction.
Why coordination across merger regimes is harder than it looks
Cross‑border merger planning often fails for non‑substantive reasons: mismatched definitions, mismatched clocks, or mismatched disclosure assumptions. Australia’s new regime magnifies those risks because it introduces a clearer statutory timetable and fee‑based escalation, which must be reconciled with other systems that do not operate the same way.
Consider three common comparator systems that regularly intersect with Australia‑linked deals.
In the European merger system, the standstill concept is explicit: under Article 7 of the EU Merger Regulation, a concentration with a Community dimension “shall not be implemented” before notification or clearance. That is a strict suspensory posture backed by the possibility of enforcement action for breach.
In contrast, in the United Kingdom, the government’s own published guidance emphasizes the voluntary nature of the merger regime: businesses do not have to tell the Competition and Markets Authority about a merger, although there can be benefits to notifying pre‑completion and the CMA may investigate on its own initiative if jurisdictional tests are met.
In the United States, the premerger notification model under the Hart‑Scott‑Rodino Act is a hybrid: certain transactions require filings to the Federal Trade Commission and U.S. Department of Justice, followed by a statutory waiting period (generally thirty days, with a shorter period in certain tender offer or bankruptcy contexts) before consummation.
These differences matter because they drive different transaction behaviors. Where a regime is mandatory and suspensory (such as the EU, and now Australia for in‑scope acquisitions), deal documents and integration planning must be drafted with tight “clean team” disciplines and strict closing mechanics. Where a regime is voluntary (such as the UK), the strategic question can be whether to notify at all—and how to quantify the risk of a regulator intervening post‑completion.
Australia adds its own distinctive features that overseas deal teams may not immediately anticipate. Notification and waiver outcomes are published on a register, and the ACCC states that reasons for approvals are published and may be followed by a calendar waiting period to allow review applications. The system also embeds a serial acquisitions lens that can require careful, consistent narrative treatment of prior deals across multiple years—precisely the type of fact pattern where cross‑jurisdiction filings can diverge if they are not centrally managed.
For Australian law firms advising either a foreign acquirer or an Australian target, the practical challenge is therefore less “How do we file in Australia?” (that is now a structured pathway) and more “How do we prevent the Australian pathway from becoming the pacing item, or the inconsistency point, in a global approvals strategy?”
How cross‑border networks strengthen Australian firms without turning the article into an advertisement
Australian law firms do not need an international platform to do excellent Australian merger work, but the new regime increases the premium on being able to orchestrate non‑Australian components at speed, with confidence on quality and process.
This is where a network model can be value-adding without displacing local leadership. As described in its own materials, the Commonwealth of Australia is now operating in a market where “international and cross-border transactions” are core client needs, and Interlegal’s model is to connect independent corporate and commercial law firms across more than forty‑five countries to provide clients access to local law knowledge in each jurisdiction.
For an Australian firm acting as lead counsel on an inbound public bid, the “network advantage” is not a generic promise of global coverage. The practical advantages tend to concentrate in a few high‑impact areas.
First, it reduces search and onboarding friction at exactly the stage when the deal clock is most fragile. When a transaction also triggers foreign filings, the time lost identifying, engaging, and aligning overseas counsel can be the difference between a clean long‑stop profile and a renegotiation.
Second, it supports consistency across jurisdictions. Australia’s thresholds and analytical inputs are revenue and transaction‑value based. Even where other jurisdictions apply different legal tests, the factual narrative, competitor mapping, and prior‑deal history will often need to be harmonized to avoid credibility problems.
Third, it can allow the Australian law firm to remain the client’s operational quarterback. Interlegal’s stated purpose is to enable local firms to tap into resources of other firms across jurisdictions, sharing local legal knowledge and client references, while remaining independent. This means the Australian firm can manage the global filing matrix, coordinate deliverables, and deliver a single integrated timetable to the client without the client feeling forced to migrate the entire mandate to a global mega‑firm simply to access foreign offices.
Finally, networks can create a more durable competitive proposition for mid‑market and specialist Australian law firms. Interlegal describes its membership as independent corporate and commercial law firms across many jurisdictions, aimed at giving clients access to high‑quality advice for cross‑border matters, and it maintains published member listings that present a curated directory of firms by country.
In a market where foreign bidders are a sizable share of public transactions (and where regulator timetables and fees are now more front‑and‑center), that kind of ready access can help Australian law firms respond faster, price more confidently, and reduce execution risk.
