The European Commission on Tuesday announced that it has opened an antitrust investigation into Google over allegations that the company has abused its dominant position in online search.
The probe comes after other search service providers complained about "unfavorable treatment of their services" in Google's unpaid and and sponsored search results, as well as alleged preferential placement of Google's own services, the commission said in a statement.
The announcement does not mean that the EU has reached any conclusions; only that it will conduct an "in-depth investigation" into the matter, it said.
Specifically, the commission will investigate whether Google has purposely lowered the ranking of unpaid search results for its competitors and given its own services more prominent placement. The EU will also investigate whether Google lowered the quality score for sponsored links, which are the factors used to determine the price advertisers pay to Google.
Furthermore, the EU will investigate whether Google imposes exclusivity obligations that prevent advertisers from placing ads on their own Web sites for competing services, as well as suspected restrictions on the portability of online campaign data to competing platforms.
"Since we started Google we have worked hard to do the right thing by our users and our industry - ensuring that ads are always clearly marked, making it easy for users to take their data with them when they switch services and investing heavily in open source projects," Google said in a statement. "But there's always going to be room for improvement, and so we'll be working with the Commission to address any concerns."
The issue dates back to February when Google announced that the European Commission told the company that it had received complaints from three companies about "whether Google is doing anything to choke off competition or hurt our users and partners." The EU has now opened a formal investigation into those complaints.
Those companies are Foundem, a French legal search engine called ejustice.fr, and Ciao! from Bing. Julia Holtz, Google's competition counsel, said at the time that two of the companies - Ciao! from Bing, a Microsoft acquisition; and Foundem - had ties to rival Microsoft. Ciao was purchased by Microsoft in 2008.
In a blog post late this morning, Google stressed that it built its search engine for users, not Web sites. "It may seem obvious, but people sometimes forget this - not every Web site can come out on top, or even appear on the first page of our results, so there will almost always be Web site owners who are unhappy about their rankings. The most important thing is that we satisfy our users," wrote Udi Manber, vice president of engineering, and Susan Wojcicki, senior vice president of product management.
Manber and Wojcicki also said Google provides "more information about how our ranking works than any other major search engine," but said that the "only constant is change."
"We've been working on this stuff for well over a decade, and in that time our search technology has improved by leaps and bounds," they concluded. "Our results are continuing to evolve from a list of websites to something far more dynamic."
In September, the Texas attorney general opened a similar investigation focused on Foundem, SourceTool/TradeComet, and myTriggers.
Editor's Note: This story was updated at 10am Eastern with details from the Google blog post.