The European Commission has notified Google that it has received complaints from three companies about about Google's practices.

The three companies that sent complaints to the European Commission the UK price comparison site Foundem, a French legal search engine called ejustice.fr, and Microsoft's Ciao! from Bing.

Google's Senior Competition Counsel Julia Holtz, wrote at Google's policy blog: "We are confident that our business operates in the interests of users and partners, as well as in line with European competition law."

Foundem is a member of an organisation called ICOMP which is funded partly by Microsoft. According to Holtz. the company argues that Google's algorithms demote their site in Google's results because they are a vertical search engine and so a direct competitor to Google. ejustice.fr's complaint seems to echo these concerns.

"We understand how important rankings can be to websites, especially commercial ones, because a higher ranking typically drives higher volumes of traffic. We are also the first to admit that our search is not perfect, but it's a very hard computer science problem to crack. Imagine having to rank the 272 million possible results for a popular query like the iPod on a 14 by 12 screen computer screen in just a few milliseconds. It's a challenge we face millions of times each day," Holtz added.

Google said that its algorithms aim to rank first what people are most likely to find useful and that they have nothing against vertical search sites.

Regarding Ciao!, they were a long-time AdSense partner of Google's. However, after Microsoft acquired Ciao! in 2008 (renaming it Ciao! from Bing) Google started receiving complaints about its standard terms and conditions. Ciao! initially took their case to the German competition authority, but it now has been transferred to Brussels.

Though each case raises slightly different issues, the question they ultimately pose is whether Google is doing anything to choke off competition or hurt our users and partners.

"This is not the case," Holtz said. "We always try to listen carefully if someone has a real concern and we work hard to put our users' interests first and to compete fair and square in the market. We believe our business practices reflect those commitments."