Already under investigation for antitrust in Europe, Google could face a broad parallel investigation of its dominant search business in the US by the Federal Trade Commission, Bloomberg said Monday quoting two unidentified people “familiar with the matter.”

The FTC is reportedly hanging back waiting for the Justice Department to decide if it’s going to challenge Google’s proposed $700 million acquisition of ITA Software, which provides the data for online airline tickets, a purchase it’s been reviewing since last July.

Depending on the DOJ’s decision, Bloomberg suggested the two agencies might negotiate for who leads the Google probe.

Microsoft filed a formal complaint with the Europe Commission last week charging Google with unfair competition in search, online advertising and smartphone software.

Last week Google and its infamous Buzz social network service also settled FTC charges of deceptive privacy practices and violating its own privacy promises, agreeing to implement a “comprehensive privacy program” and submit to third-party privacy audits every two years for the next 20 years.