Yesterday's announcement shows a potential investigation is at its earliest stage. Vestager is simply asking the question of retailers who use Amazon. She wants to know if any will come forward to allege that Amazon has used the data it collects from their sales to compete against them unfairly.
I suspect at the bottom of all of this is whether Amazon has ever used the data to spot new items it could be stocking itself but, perhaps more importantly, if it is using its knowledge of what others are selling items for so it can ensure it always appears a little cheaper and at the top of product search results.
As The Drum points out, and this is an important aspect, the European Commission is proactively looking for people to complain. The backstory is that it believes this practice is going on, having apparently looked into online retail previously.
Vestager is following up a hunch here. It's not a bolt out of the blue, it's not something she's made up off the top of her head, but it's a very different investigation from Google.
The latter, on search at least, took several years of complainants banging on the door of the European Commission to do more about what they considered to be the search giant acting in an anti-competitive way. It took the European Parliament to tell the Commission to pull up its socks and take action before things got serious with Google. The Android case then followed with a record GBP3.9bn fine for requiring Android developers to include its apps by default.
The European Commission is on the front foot here. It has secured record fines and it is now so confident, it is asking retailers to reveal whether its hunch Amazon requires investigation is valid or not.
Regular readers will know that I believe much of this is related to Europeans considering that the tech giants are fundamentally wrong to make huge profits out of their markets without paying their fair share of tax. Amazon asserts that it now pays its UK tax bill in full in the UK. However, there has amassed a sense of outrage in Europe over how the tech giants have behaved.
Whether it is fining Apple for back taxes or Facebook for fibbing over sharing data with Whatsapp, or the huge fines Google has been hit with, the outrage that has built up against the tech giants shows no sign of abating.
Which leaves us with the European Commission's competition watchdog giving retailers until the second week of October to complain about Amazon. It's a far cry from the days when complainants had to wait a decade to be heard, now they're being sought out.
Amazon, watch out. You're next.