Market concentration has been increasing globally over the past few decades. New US research has suggested that as much as half of this increase may be explained by undisclosed merger activity involving smaller companies.

New research by the e61 Institute assesses a change in the 2008 Australian merger guidelines, finding:

• The change resulted in the number of deals reviewed decreasing by 75%.
• A significant portion of this decrease came from deals that were not publicly notified.
• The average time spent reviewing a deal also doubled after this change, suggesting greater resources were spent on larger transactions.

With Australia’s voluntary disclosure regime, smaller transactions are potentially leaving blind spots in our understanding of the competitive landscape in Australia.

An important starting point for merger reform in Australia will be obtaining a clearer picture of merger activity.