Key changes to automatic voiding, stale clearances and the joint control test 2 min read
On 16 September 2026, some important amendments to Australia's mandatory merger regime came into effect.
The amendments address practical concerns raised by stakeholders following the introduction of the new mandatory merger control regime, in particular that the regime was over-inclusive and may encourage precautionary filings.
We've outlined the key changes below.
Automatic voiding
Previously, a notifiable acquisition completed without notification was automatically void, regardless of whether the failure to notify was inadvertent, whether the Australian nexus was limited or whether the transaction raised any substantive competition concerns.
The amendments replace automatic voiding with a court-supervised process. The ACCC must now apply to the Federal Court for a declaration that a non-notified acquisition is void. The Court must make that declaration unless it considers doing so would be undesirable, for example, where unwinding the transaction would cause significant prejudice to innocent third parties or would be impracticable. Importantly, the Court cannot consider the substantive competition merits of the acquisition when deciding to make a voiding order. The ACCC retains the ability to seek orders to address the consequences of a non-notified acquisition, including divestiture orders and orders concerning the transfer of assets or title.
The amendments also do not alter the position for transactions that have been notified but are implemented before ACCC clearance is obtained (ie, gun-jumping), which will continue to be automatically void.
Stale acquisitions
The amendments introduce a mechanism allowing parties to apply to extend ACCC clearances that would otherwise lapse after 12 months. If the merger has not completed within that period, the clearance becomes ineffective and the parties would ordinarily need to submit a fresh notification.
Under the amendments, the ACCC may grant extensions of up to six months at a time, with no statutory limit on the number of extensions. In deciding whether to grant an extension, the ACCC must consider factors including whether there is a reasonable explanation for the delay, whether market conditions have materially changed since the ACCC granted clearance, and whether a fresh notification would be more appropriate.
Importantly, this extension mechanism applies only to formal ACCC clearance decisions under the new merger control regime. It does not apply to section 189 letters issued during the transition period between 1 July 2025 and 31 December 2025. Where completion occurs more than 12 months after the ACCC issued a section 189 letter, parties will generally need to seek a waiver or submit a notification to the regulator before proceeding with the acquisition.
Joint control
The amendments also address some concerns regarding the breadth of the control test. Previously, there was a risk that shareholders could be treated as associates with joint control merely by being party to a shareholders' agreement containing standard governance provisions, even where they lacked any meaningful ability to influence the target's competitive conduct.
The amendments narrow the circumstances in which parties will be treated as associates and clarify that ordinary minority shareholder protection rights will not, by themselves, constitute joint control. Instead, control or joint control will require practical influence over operational or financial matters, for example, through rights relating to the appointment of directors or veto rights over strategic matters such as budgets and business plans.
These changes bring Australia's approach more in line with the concept of joint control under the European Union Merger Regulation.
However, acquisitions that cross the relevant voting power thresholds still require notification regardless of whether control is acquired (if the monetary and 'connected to Australia' thresholds are met), and the revised definition of associate has not been extended to voting power. In that context, minority investors must still consider the voting power thresholds and whether their voting power is aggregated with that of non-minority shareholders.