Legislative reforms to overhaul the merger control regime in Australia have been passed by the federal parliament. The reforms will fundamentally reshape merger control processes in Australia and include:

• A shift from the current voluntary notification regime to a mandatory and suspensory model. Under the regime, acquisitions that meet the notification thresholds must be notified to the ACCC.
• The ACCC will become the primary decision maker, a change from the current model where the ACCC is principally an enforcer that requires the decision of a court to formally 'block' a transaction.
• Rather than the current voluntary model, failure to notify and obtain clearance when required will mean the transaction is void and the ACCC may bring proceedings seeking penalties. The suspensory nature of the regime prevents the parties closing before clearance has been obtained.
• While the test applied will largely remain unchanged, there will be some differences. First, the test (whether the acquisition is likely to have the effect of substantially lessening competition) will be expanded to enable the ACCC to consider if the acquisition will 'create, strengthen or entrench' a position of substantial power in any market. Second, to target creeping acquisitions and roll-up strategies, when assessing an acquisition the ACCC will be able to have regard to all acquisitions by the parties in the prior 3 years involving the same or competitive goods or services.
• There will be greater timing certainty, with fixed times in which the ACCC is required to make a decision. The regime also includes various 'off-ramps' to allow for prompt decisions regarding uncontroversial acquisitions. There will be scope for pre-engagement with the ACCC and it remains to be seen if that 'pre-clock' phase will, in practice, result in a longer engagement process.
• The regime will introduce other process changes that will be significant in the context of some deals. For example, there will be greater transparency, with notified acquisitions listed on a public register (subject to some minor exceptions). Filing fees (yet to be announced) will apply, which are likely to be staged depending on the complexity of the review with exceptions (small business).

We have previously provided a detailed outline of the reforms as they were introduced into parliament in our article Brave new world: Mandatory merger control in Australia. The legislative package passed by the parliament is unchanged. We have also provided additional detail, including context regarding the broader merger control landscape in Australia in the Global Competition Review's – Market Review: Merger Control 2024. For those who cannot access the guide, please contact us – we would be pleased to share a copy.

What comes next?

There are a few remaining 'known unknowns' where we are still awaiting further details – these include:

• Notification thresholds – Treasury has provided some detail regarding the proposed notification thresholds that will apply. However the final form of the thresholds will be contained in regulations made under the new legislation. We expect this critical piece of the puzzle to be released shortly.
• Filing fees – While the filing fees have not yet been confirmed, explanatory materials that accompanied the bill indicated that Treasury expected them to be in the range of A$50,000 - A$100,000 per transaction, with exemptions applying in some cases (e.g. for small business).
• Further ACCC forms and guidance – the ACCC has indicated that it will provide further guidance during the course of H1 2025 to provide information about how the regime will operate in practice. This will include application forms setting out the information and documents that must be provided, details regarding the waiver notification process, and substantive guidance about the ACCC's processes and approach.

When will the new regime commence?

The complete mandatory and suspensory regime will commence from 1 January 2026. However, the regime provides for a series of transitional arrangements that include:

• Merger authorisation applications under the current regime will be accepted until 30 June 2025 – applications submitted before this date will continue to be considered until the ACCC or Tribunal makes a determination.
• Voluntary filings under the new regime will be available from 1 July 2025. This will allow parties to 'opt-in' to the new regime as the commencement of the new regime approaches. It will also allow parties to continue to make public benefit arguments in appropriate cases once the merger authorisation process has 'closed'.
• Parties will be able to continue notifying transactions under the current informal regime until 31 December 2025. The ACCC will provide further guidance and engage with merger parties in relation to merger reviews under the informal process that remain ongoing at 31 December 2025.
• Transactions that the ACCC considers and does not object to under the informal merger review process between 1 July 2025 and 31 December 2025 will not require a new notification, provided completion occurs within 12 months of the ACCC's decision.
• The complete mandatory and suspensory regime will commence in full from 1 January 2026. Importantly, it will apply to acquisitions closing after 1 January 2026. Parties will therefore need to carefully consider transitional pathways for deals signed in 2025 that may not complete until 2026.

What this means for business and deal activity

The reforms passed by the Australian parliament will significantly alter the process for notifying and engaging with the ACCC. It is essential that businesses – particularly those considering an active growth or exit strategy – understand the operation of the regime.

Businesses will want to consider:

• The effect on timing, including optionality that will arise as part of the transitional arrangements.
• Implications for deal processes (including timelines in process letters), and adjustments in relation to due diligence practices – this will include reverse due-diligence regarding notification obligations.
• Changes required to transaction documents including the approach to conditions precedent and an increased focus by the ACCC regarding restraints / non-competes contained in sale agreements.

We are working closely with our clients to prepare for the reforms. Questions? Our Competition Team is ready to help – get in touch if you would like to discuss the reforms and what they will mean for your deal strategy and pipeline.