Google has changed how shopping results appear so shoppers can now see goods from price comparison sites as well as its own results.
Google’s appeal against a huge fine imposed by the European Commission over its alleged abuse of power in promoting its own shopping comparison service will be heard over the next three days.
The hearing will take place at the General Court in Luxembourg.
The €2.4bn ($2.6bn; £2bn) fine was handed out in 2017 and the search giant has always vowed to fight it.
It argues that the case has no legal or economic merit.
In a statement to the BBC, Google said: “We’re appealing [against] the European Commission’s 2017 Google Shopping decision because it is wrong on the law, the facts, and the economics. Shopping ads have always helped people find the products they are looking for quickly and easily, and helped merchants to reach potential customers.
“We look forward to making our case in court and demonstrating that we have improved quality and increased choice for consumers.”