On April 20, 2007, CDD, EPIC and US PIRG filed a complaint (pdf) with the Federal Trade Commission, requesting that the Commission open an investigation into the proposed acquisition, specifically with regard to the ability of Google to record, analyze, track, and profile the activities of Internet users with data that is both personally identifiable and data that is not personally identifiable. The three groups filed a supplement (pdf) to the complaint with the Commission in June.

On September 17, 2007, at the National Press Club, the Center for Digital Democracy, EPIC and US PIRG announced a second supplement (pdf) to the groups' original complaint (pdf) and subsequent supplement (pdf) with the FTC concerning the proposed Google-DoubleClick merger. The amended complaint detailed new facts supporting the conclusion that the FTC should block Google's proposed acquisition of DoubleClick.

The FTC has made a "second request" in its review of Google's merger with DoubleClick (the world’s largest Internet advertising technology firm). According to FTC Chair Majoras's statement (pdf) on the merger review process, "the majority of investigations in which the FTC issued a second request resulted in a merger challenge, consent order, or modification to the transaction, suggesting that the FTC generally issues second requests only when there is a strong possibility that some aspect of the investigation would violate the antitrust laws."