LONDON — Europe’s five-year antitrust investigation against could soon be heating up again.
The has asked several companies that had filed complaints against the search giant to make their confidential submissions public, according to several people with direct knowledge of the matter who spoke only on the condition of anonymity because they were not authorized to speak publicly.
The companies that have filed submissions with the commission include major American technology companies, like Yelp, as well as powerful German and French publishing groups that claim Google has too much control over how Europeans access information over the Internet. By asking several of these companies to make their submissions public, the European Commission can ask Google to respond to the companies’ claims and bring the case closer to resolution, according to several of the people.
The move is part of the continuing investigation by Europe’s antitrust officials into whether Google has used its dominant position — the company controls roughly 90 percent of the region’s online search market — to give preferential treatment to its own services.
The case represents a litmus test for Margrethe Vestager, Europe’s new antitrust chief, who took over late last year and has been tasked with deciding whether to reach a settlement with Google or to push forward with formal charges.
Officials and analysts warned, however, that it was still unclear whether the European Commission would file charges against Google. They added that the recent requests to companies like Yelp, which competes with Google to offer online reviews to consumers, to publish their complaints could not be seen as definitive proof that officials would push forward with charges.
Representatives for Google and the European Commission declined to comment.
Ms. Vestager met with Eric Schmidt, Google’s executive chairman, in Brussels last month to discuss the case, according to a person with direct knowledge of the matter.
Joaquín Almunia, Ms. Vestager’s predecessor, to reach an agreement with Google, but was widely criticized by other European politicians for offering too lenient terms that would have allowed the search giant to continue many of its current practices.
Europe’s financial penalties against Google could be substantial. Officials have the power to fine Google up to 10 percent, or roughly $6.5 billion, of its most recent annual sales and to place restrictions on the company’s operations in Europe.
“Everyone is very aware that this case has to come to some sort of conclusion,” said Mario Mariniello, a researcher at the think tank Bruegel in Brussels and a former antitrust official. “The pressure is rising. They will have to come to some sort of decision soon.”
The Wall Street Journal that Europe’s antitrust officials had asked companies to make their complaints against Google public.
The antitrust case comes as the Federal Trade Commission is facing over how it handled its own competition investigation into Google.
A recently released internal report by the agency suggested that Google should sue for antitrust practices, though the agency decided in 2013 not to bring charges.
In Europe, however, many politicians have taken a harder line against the perceived dominance of many American tech companies like Google and Facebook, and have been willing to intervene and impose fines if companies are viewed to hold too much sway.
“It’s acceptable that some companies have dominant positions,” Andrus Ansip, the European Commission’s digital chief with The New York Times last month, adding that, “if there are doubts that they are abusing their dominant position, of course, the European Commission will be there to intervene.”