Company that has complained to the European Commission about other Google practices alleges that the search giant blocked some of its rivals from using AdSense.
The EU competition commissioner Joaquin Almunia says the case is "complex" and his office is in no hurry to decide if it should launch a formal antitrust complaint against Google.
Regulators to probe whether Google abused its dominant position as a search engine by unfairly favoring its own services in search results over those from competitors.
The online travel site says Google is engaging in "unfair practices." The move follows a similar one by Expedia, which filed an antitrust complaint last week against the search giant.
The software company reportedly complained about Google+, but has publicly denied any claims that it filed a complaint against the social network.
Google's search algorithm is coming under scrutiny by the European Commission after other search engines complained they're being unfairly axed from its results.
The European Competition Commissioner Joaquin Almunia tells Reuters the decision to file a formal complaint against Google could happen as early as March.
While the Internet giant and trustbusters prepare for a year of hearings and court battles, some legal experts are struck by the similarities of what Microsoft faced a decade ago and Google faces today.