Topaz's plunge for Esso Ireland looks like it will be the first big test for the newly minted Competition and Consumer Protection Commission (CCPC).

Somewhat ironically, given that part of its job will be to police mergers, the commission was itself formed by merging the Competition Authority and National Consumer Agency.

The change also involved a revision of the thresholds that determine whether a takeover should be reviewed before it can go ahead.

That will make little difference to the Topaz-Esso deal, as the buyer has €3 billion sales while the target has €455 million in revenues, ensuring that it would also have come under the old regime’s spotlight.

The old regime also has a precedent of sorts for this case in the shape of Topaz's takeover of what was then the Statoil service station network in the Republic.

While that was mired in confusion, it ultimately resulted in the Denis O’Brien-owned fuel business having to sell a terminal in Galway and a service station.

That is not to say that it will do the same thing this time around, or anything like it. That deal was eight years ago and the market could well have changed.

The salient points, such as market share and barriers to entry, are likely to occupy the commission, as will the fact that Topaz is acquiring a distribution business and a half share in a terminal in Dublin Port, where it already owns another.

The commission could also look at local or regional concentrations of ownership.

Whatever happens, it will be aware that there will be plenty of interest in its findings.

It will also be keen to avoid the mistake made with the Statoil deal, which the Competition Authority inadvertently cleared after miscalculating the deadline by which it had to complete its review of that transaction.