By Dr Brett Davies, Adjunct Professor, UWA, Adjunct Reader, Managing Director of the PLT course by the Institute of Legal Training (IOLT)

In the high-stakes world of corporate finance, we often get lost in the takeover jargon. We talk about “synergies” and “accretive value.” But for the average Australian, what does this actually mean?

To start from ground zero: a merger is effectively a corporate marriage. Two companies combine their assets, staff, and operations to become a single, more powerful entity. On paper, this sounds like good business. It can lower costs and improve efficiency.

However, there is a dark side. If two large competitors merge, they can become a monopoly. When one company holds all the cards, it can dictate prices to suppliers and families.

This is where the Australian Competition and Consumer Commission (ACCC) steps in. The ACCC is the market’s referee. Its job is to ensure that business ambition does not crush the “fair go.”

The Historical Context of Approving Mergers in Australia: The “Voluntary” Flaw

For decades, the process of notifying this referee was effectively a handshake. While section 50 of the Competition and Consumer Act 2010 (Cth) has long prohibited deals that substantially lessen competition, the mechanism for pre-completion notification and clearance was largely voluntary.

As of 1 January 2026, that era was over. The Competition and Consumer (Notification of Acquisitions) Amendment (2025 Measures No 1) Determination 2025 (Cth) was registered on 18 December 2025.

The regulator fought an uphill battle under the old system. This is illustrated by the landmark Metcash case (ACCC v Metcash Trading Ltd [2011] FCAFC 151).

When Metcash proposed buying Franklins, the ACCC argued it would crush competition. It lost. The Full Federal Court held the ACCC failed to establish the “counterfactual”—effectively, the regulator could not prove, on the balance of probabilities, that a more competitive alternative would occur if the merger was blocked.

This case exposed the practical height of the evidentiary bar. It meant that companies could engage in “killer acquisitions”—buying small competitors before they became a threat—without facing any mandatory pre-completion review.

The New Australian Merger Rule: Permission, Not Forgiveness

The Federal Government has now registered the Competition and Consumer (Notification of Acquisitions) Amendment (2025 Measures No 1) Determination 2025 (Cth). This instrument turns the new framework into reality.

The regime flips the dynamic. Notification is now mandatory and suspensory under the rules, with completion prohibited until clearance is granted.

Transparency is the default. All notified acquisitions will appear on a new public ACCC acquisitions register, listing the parties, status, and outcomes. The days of the quiet, informal chat are gone.

However, the Government has adopted a phased approach:

• 1 January 2026: The core regime started.
• Transition Window: Critically, share acquisitions that do not result in control are exempt from notification until 31 March 2026.
• 1 April 2026: The full suite of rules applies, including expanded definitions of control and specific new thresholds for asset acquisitions.

Here is how the new rules hit the ground in practice.

Scenario 1: The “Creeping” Takeover Acquisition (The Roll-Up)

Consider a large national corporation buying small competitors.

• Old World: It buys twenty small family businesses over three years. Each deal is small, so the ACCC is rarely notified.
• New World: The new rules catch “serial acquisitions.” The system now looks back at all acquisitions in the same or substitutable market over the last 3 years. If your cumulative turnover meets the serial threshold—$50 million for large firms or just $10 million for very large acquirers—it triggers a mandatory notification for your next purchase. The “roll-up” strategy now happens in broad daylight.

Scenario 2: The WA Resource Trap when it comes to mergers and acquisitions

This is where the view from Western Australia is distinct. The regime uses a sophisticated tiered threshold system:

1. General Test (Large Merged Firms): Notification is required if the combined Australian turnover of the merger parties is ≥ $200 million AND either:
   • The target’s Australian turnover is ≥ $50 million; OR
   • The global transaction value is ≥ $250 million.
2. Very Large Acquirers: For acquirers with Australian turnover > $500 million, the threshold drops significantly. They must notify if the target’s turnover is ≥ $10 million (or if cumulative serial turnover is ≥ $10 million).
3. Designated Supermarket Corporations (Coles and Woolworths): Strict rules apply specifically to Coles and Woolworths. They must notify all acquisitions of supermarket businesses. Furthermore, they must notify land acquisitions exceeding 1,000 square metres of gross lettable area (if built) or 2,000 square metres (if vacant), unless specific exemptions like lease renewals apply.

• The WA Risk: In Sydney, a company with under $10 million in revenue is a small business. In the Pilbara, a junior miner might have $0 revenue but sit on a $1 billion critical mineral deposit.
• The Policy Gap: While the tiered system is comprehensive, a “turnover” test can still miss the strategic value of WA resources. As a practitioner, I argue that the regime may eventually need to look beyond the profit and loss statement to the balance sheet to protect national interests.

Scenario 3: The Property Developer engaging in mergers and takeovers

For my clients in property, the “Ordinary Course of Business” exemption is the vital lifeline.

• Exempt: The exemption applies broadly to genuine ordinary course activities, such as land acquisitions for development or commercial leases. It is assessed on the facts, including the nature of the transaction.
• Caught: However, exemptions do not cover targeted sectors like supermarkets. Even if you claim a lease is “ordinary course,” if you are a major supermarket chain acquiring a site, specific rules likely pull you back into the mandatory notification zone. It is a fact-dependent test, not a blanket pass.

The Butcher’s Son: A Question of Fairness when it comes to stopping monopolies

The shift to a mandatory regime is not just red tape. It is about addressing the procedural limitations highlighted by cases such as Metcash.

I view this through the lens of my own history. I am the son of a butcher. I was the first in my family to attend university. I know that when the rules are loose, the small players—the families and independent businesses—often get squeezed out.

The Commonwealth has built a robust fence. The challenge now is to staff the gate with regulators who understand both the legal nuance and the commercial reality.

References

• Treasury Laws Amendment (Mergers and Acquisitions Reform) Act 2024 (Cth).
• Competition and Consumer (Notification of Acquisitions) Amendment (2025 Measures No 1) Determination 2025 (Cth).
• Competition and Consumer (Notification of Acquisitions—Forms) Determination 2025 (Cth).
• Australian Competition and Consumer Commission v Metcash Trading Ltd [2011] FCAFC 151.