The US government's Federal Trade Commission has approved Google's acquisition of DoubleClick, the Associated Press reports. The two signed a deal in April worth $3.1 billion, but the purchase has since undergone much scrutiny, primarily due to worries that Google might develop a monopoly in online advertising. This opinion was voiced especially strongly by Microsoft and AT&T, despite the former of the two having bought the ad firm aQuantive. Microsoft is pushing heavily into areas currently ruled by Google, such as web search and mapping.

The FTC has dismissed antitrust concerns, accepting Google's position that its online advertising sales do not directly compete with DoubleClick, which develops ad-serving tools. The acquisition is not quite complete, however, as it still requires approval by the European Commission, which has only set an April 2nd deadline.

The deal has also drawn harsh words from privacy advocates, who note that the combination of Google's current user tracking with information from ad views could give the company a massive amount of information about individual habits. The FTC today proposed a set of privacy guidelines for online advertising, but this has not satisfied NGOs such as the Center for Digital Democracy, which argues that the FTC has "sidestepped its responsibility."