What Is the ACCC, and Why It Just Changed Every M&A Deal in Australia

Australia's biggest competition law overhaul in fifty years took effect on 1 January 2026. Documentation, timelines, and penalties all moved in the same direction. The operational consequences are larger than the headline suggests.

The ACCC is the Australian Competition and Consumer Commission — Australia's federal competition regulator, the rough equivalent of the US FTC and DOJ Antitrust combined, or the UK's Competition and Markets Authority.

On 1 January 2026, Australia's merger control regime moved from voluntary to mandatory and suspensory. Deals that hit the new thresholds must be notified to the ACCC and cannot close until the ACCC clears them. Closing without clearance can void the transaction and trigger civil penalties.

For acquirers, three things changed at once: the documentation burden, the review timeline, and the cost of getting either wrong. Each one has operational consequences that start on the day the deal is signed, not the day the regulator asks.

The Regulator

What the ACCC actually is

The Australian Competition and Consumer Commission is the federal authority that enforces Australian competition law and consumer protection. It investigates anti-competitive conduct, brings actions against firms that abuse market power, and — the function most relevant here — reviews mergers and acquisitions for their effect on competition.

Until the end of 2025, the ACCC's role in M&A was primarily advisory and litigative. Acquirers could voluntarily seek the ACCC's view on a proposed deal through informal review, but they were not required to. If the ACCC believed a deal would substantially lessen competition, it had to sue in Federal Court to block it — an expensive, slow, and uncertain remedy. Most deals just got done.

That model has now ended. The Treasury Laws Amendment (Mergers and Acquisitions Reform) Act 2024 and the Competition and Consumer (Notification of Acquisitions) Determination 2025 together establish a new Part IVA of the Competition and Consumer Act 2010, replacing the informal review and merger authorisation processes with a single mandatory administrative regime. The ACCC is now the administrative decision-maker on every notifiable deal, not a litigant after the fact.

The Change

What took effect on 1 January 2026

Two words define the new regime. The first is mandatory: if a transaction meets the notification thresholds, the parties must notify the ACCC. There is no opting out, and no informal alternative. The second is suspensory: a notifiable deal cannot be put into effect — cannot close — until the ACCC has approved it. Closing before clearance renders the transaction void by operation of law and exposes the parties to substantial civil penalties.

This is the most consequential change to Australian competition law since the original Trade Practices Act in 1974. Under the prior regime, an acquirer could choose to engage the ACCC, choose not to, or close and risk a Federal Court challenge. None of those options exist for notifiable deals now. The default has been inverted.

The thresholds, in plain terms

A transaction is notifiable if it has a connection to Australia and meets any one of the following monetary tests. (Acquisitions of land, certain ordinary-course transactions, and internal restructures are generally outside scope; specific carve-outs apply.)

Threshold details for asset acquisitions that are not all-or-substantially-all of a business were further amended by Treasury and take effect from 1 April 2026. New control-related thresholds also commence on that date. Deal teams should treat both Q1 and Q2 of 2026 as live transitions.

The timeline, in plain terms

The ACCC encourages pre-notification engagement — submitting a draft notification, working through the data requirements, and resolving information gaps before the formal clock starts. The regulator recommends two weeks for straightforward matters and at least four weeks for complex ones. Phase 1 review then runs up to 30 business days from effective notification; Phase 2 review, if triggered, runs up to a further 90 business days.

In practice, a complex deal that previously closed in 60 days now spans four to six months from contract signing to completion. A clean deal can close faster, but the planning baseline has shifted. Pre-notification, Phase 1, and any Phase 2 are not optional; they are the default path for any transaction that meets the thresholds.

The Consequences

Three operational shifts that hit on day one

• Documentation burden, materially up. The ACCC's notification forms — short, long, and waiver — require structured information about the parties, the transaction, the affected markets, and the competitive effects. The ACCC can request internal documents, and under the new creeping-acquisition provision, it can examine all transactions of a party valued over A$2M and connected to Australia in the prior three years. For acquirers, this means the deal file is now a public regulatory artefact, not just an internal one. Buyers need clean, defensible records of their own systems and operations on contract date, and equally clean records of the target's systems for the period of the ACCC's review and beyond. Patchy or improvised inventories are a notification risk.
• Timelines, materially up — and so are the carrying costs. Four to six months between signing and completion is four to six months in which the buyer pays maintenance, licensing, security, and integration costs on systems they are likely to retire post-close. On a typical mid-market deal, that period covers ERP licensing renewals, security patch cycles, support contracts, and at least one quarterly close run on the target's legacy environment. Acquirers used to defer the “what do we do with the legacy stack” conversation until completion. Under the new regime, that conversation now sits inside the deal window, alongside the regulatory review. The economic cost of not deciding is higher than it was. So is the operational risk of arriving at completion without a plan.
• Penalties, materially up — and the deal can be void. Closing a notifiable transaction without clearance is a breach of Part IVA of the Competition and Consumer Act and renders the transaction void. Substantial civil penalties may apply to the parties. Providing false or incomplete information to the ACCC during the notification process carries its own consequences. The ACCC publishes notifications and waivers on a public register, and details appear within one business day of notification. The risk profile that buyers underwrite has changed. What you do not know about the target's systems — the records you cannot produce, the data you cannot inventory, the lineage you cannot reconstruct — is now visible to the regulator, the market, and the seller's counsel. Buyers are appropriately more risk-averse about discovery gaps than they were a year ago.

Why This Matters for Solix Customers

Application archive becomes a day-one decision, not a post-close one.

What Solix's archival and application retirement platform enforces in this category is the part of an M&A integration that the new regime made structurally harder: the safe end-of-life of a target's legacy systems with their records, schemas, and audit evidence intact, retrievable independently of the source system, defensible to a regulator years after the source has been shut down.

For an acquirer in the new regime, the operational sequence shifts. Archive on signing, not on completion. Take inventory of the target's systems while the ACCC review runs. Produce evidence quickly when the regulator asks for it. Defer the retirement decision — but not the archive decision — until after clearance, with the maintenance bill on the legacy stack scoped against an actual end-of-life path rather than an open-ended carry.

For SAP ECC and Oracle E-Business Suite consolidations, custom application sunsets, and the long tail of post-acquisition system rationalisation, the same model applies. Capture the records under policy, retain them past the lifespan of the source, retrieve them independently when the request comes — whether the request comes from the ACCC, from internal audit, or from a customer dispute three years after close.

Three things to do this week

• Walk one in-flight deal through the new threshold tests. Pick a transaction currently on your desk. Apply the combined revenue, transaction value, and very-large-acquirer tests. The exercise reveals which deals in your pipeline are now notifiable that would not have been a year ago. Most M&A teams find more than they expect — particularly when the three-year creeping-acquisition aggregation is applied to acquirers with prior bolt-ons.
• Map the carrying cost of the target's legacy stack across a six-month review window. Total maintenance, licensing, security, and support spend on systems your post-close plan will retire. Multiply by the number of months between expected signing and completion under the new regime. The number is usually material enough to fund a day-one archival plan with margin to spare. The conversation about when to retire becomes a conversation about when to archive.
• Treat the ACCC notification as a discovery requirement on the buyer, not a paperwork exercise. The ACCC will publish notifications, request internal documents, and aggregate prior transactions. Buyers that arrive at the regulator with clean inventories, documented data lineage, and a defensible records position move through Phase 1 faster and avoid Phase 2 escalation. The records discipline that produces a clean notification is the same discipline that produces a clean integration. Build it once.

References

• ACCC (Australian Competition and Consumer Commission) — Merger control regime. Official guidance on the regime that took effect 1 January 2026.
• ACCC — Thresholds for notifying acquisitions. Authoritative summary of the monetary tests, exemptions, and supermarket-specific requirements.
• Norton Rose Fulbright — Australia's new mandatory merger control regime. Detailed legal analysis of the substantive test, control thresholds, and creeping-acquisition provisions.
• Gilbert + Tobin — Australia's new merger regime: what you need to know. Practitioner guide to notification process, fees, and the choice between waiver, short form, and long form notifications.
• Ashurst — Australian Merger Reforms. Practical guide including pre-notification engagement, timeline expectations, and how the regime is functioning four months in.
• Herbert Smith Freehills Kramer — Treasury Updates Merger Rules. Analysis of the December 2025 Determination and the additional changes commencing 1 April 2026.