The Australian government is planning a mandatory notification regime for significant corporate mergers to curb market concentration and enhance competition.

Treasurer Jim Chalmers is set to outline these reforms aimed at increasing transparency and preventing anti-competitive mergers.

The reforms are part of a broader strategy to promote productivity and innovation within the Australian economy.

Updates to the merger laws will address serial acquisitions and streamline the merger review process.

ACCC chair Gina Cass-Gottlieb supports the changes, which will empower the ACCC to more effectively scrutinize and intervene in potentially harmful mergers.

The new laws will distinguish between mergers that are beneficial and those that could lead to market dominance, targeting specifically 'creeping acquisitions'.

The introduction of cost recovery fees for merger assessments will accompany the reforms, with small businesses being exempt.

Pending parliamentary approval, these reforms are set to be implemented in 2026 and represent the most significant business reform in Australia since the 1970s.