The Federal Trade Commission (FTC) is expanding its investigation into Google's purchase of AdMob, reports Bloomberg.
Citing anonymous sources "with direct knowledge of the matter," Bloomberg said the FTC is seeking affidavits from at least two companies and is going after statements from Google's competitors and advertisers.
The news could indicate that the FTC may challenge the AdMob acquisition on the grounds that it may prove anticompetitive, although it is not unusual for the agency to investigate without enacting legal proceedings.
Google did not respond to requests for comment by press time, but acknowledged in late December that it had received a second request from the FTC for further information on the deal.
Google and AdMob combined would form the largest mobile advertising company – the companies combined had 21 percent of the U.S. market in 2009, according to Karsten Weide, an analyst with researcher IDC in San Mateo, Calif.