Despite allegations of 'conflicting interests' the U.S. Federal Trade Commission (FTC) has said it will not block Google’s purchase of online ad-serving vendor, DoubleClick.

The Commission voted 4-1 to approve the deal after an eight-month investigation. However, the decision is considered somewhat controversial because the Chairman of the FTC, Deborah Platt Majoras, was found to have links with the legal firm representing Doubleclick in the EU. She refused to step down.

The FTC said that after carefully reviewing the evidence, it had concluded that Google’s proposed acquisition of DoubleClick was unlikely to substantially lessen competition. It also downplayed concerns brought by privacy groups saying that the issues were not unique to Google and DoubleClick.