Finding a needle in a haystack: identifying the local markets that matter

In June 2026, the Australian Competition and Consumer Commission (ACCC) approved Ampol’s acquisition of EG Australia subject to a 41-site divestiture undertaking. It was the first transaction referred to Phase 2 under Australia’s new merger regime.

One statistic stands out. The ACCC assessed 1,134 local markets and identified concerns in just 39 - approximately 3.4%.

The other 1,095 still had to be screened and set aside on a defensible basis. That is the practical challenge for advisers working on mergers involving hundreds of local overlaps: identifying where detailed assessment is required, without spreading time and attention evenly across the entire portfolio.

Why the easy 97% still takes work

The ACCC began with an independent dataset of fuel-retail sites, which it refined using information from the parties and its own industry knowledge. It then examined local competitive conditions using several parameters, including straight-line radii of between three and ten kilometres and five- and ten-minute drive-time catchments.

These catchments provided consistent analytical lenses through which to test the evidence. The relevant geographic market remained part of the wider substantive assessment.

The underlying data can be equally decisive. A missing or misclassified competitor may affect the concentration figures for every overlapping site nearby. A different but plausible catchment may also move a location above or below a screening threshold.

Running alternative scenarios reveals which conclusions remain stable across reasonable assumptions. It also exposes the markets where the initial view is most vulnerable to challenge.

From shortlist to substantive assessment

The ACCC focused its attention on markets with a post-acquisition site share above 40% or an HHI above 2,000. Applying those screens across the portfolio produced a manageable set for closer review.

The detailed assessment then considered proximity, site characteristics and whether the remaining competitors represented realistic alternatives. Two locations with identical concentration figures may present materially different competitive conditions. A nearby competitor might sit across a motorway, serve a different traffic flow or lack the characteristics that make it a meaningful alternative.

Concentration metrics create the shortlist. Legal and economic judgment explains the result.

Remedies change the analysis

Ampol proposed divesting 19 sites when it notified the transaction. The package increased to 37 sites during Phase 2 and ultimately to 41.

Each iteration changed the competitive picture and had to be tested against the markets that raised concerns. Earlier modelling gives the parties more time to compare possible packages, understand which concerns each package resolves and minimise unnecessary commercial disruption. Once an authority’s position has hardened, the available options may already be narrowing.

What this means for practitioners

The Ampol decision points to four practical lessons:

• Get the portfolio-wide analysis under way early. Build and reconcile the site universe before data gaps become time-critical.

• Use screens to direct adviser time. Apply shares and concentration measures consistently across the portfolio, then focus detailed assessment on the locations that warrant it.

• Stress-test the assumptions. Identify conclusions that change under another plausible catchment or treatment of the data before they become points of regulatory challenge.

• Model remedies before positions harden. Test divestment options while the parties still have time and commercial flexibility.

Software can absorb much of the repeatable work involved in updating datasets, rerunning catchments, recalculating screens and testing remedies. Sloc supports that workflow within a single, traceable analysis, while the legal team retains control over the inputs, assumptions and substantive conclusions.

The practical goal is early, confident identification of the 39 markets that deserve detailed attention, supported by a clear basis for setting aside the remaining 1,095.