Google faces fresh inquiry from FTC The US Federal Trade Commission has begun an informal inquiry into Google's display advertising business, opening a new front in the internet search company's antitrust battles just months after it appeared to resolve earlier investigations on both sides of the Atlantic. The regulators are probing areas of the display advertising market where Google has had a leading presence since its acquisition of display ad company DoubleClick in 2007, according to several people familiar with its research. The FTC warned at the time of that deal that it would look again if it suspected Google was abusing its new-found power in display. Among the issues under review are whether Google uses its dominant position in ad serving, or distributing advertising on behalf of online publishers, to drive business to its in-house advertising exchange. That practice, which it promised not to engage in at the time of the DoubleClick acquisition, risks hurting other companies like Yahoo that have tried to build exchanges of their own. The prospect of the fresh investigation was first reported by Bloomberg The FTC has sought detailed information about a range of Google's practices in display advertising, according to two digital ad executives who said their firms had been contacted by the FTC. Other questions raised include whether Google prohibits companies using other ad serving services from using its exchange, according to one of these people. However, the regulators" chances of building a case against Google for abusing its power in display ads appear slim, particularly given its recent decision not to pursue Google over search advertising, according to two people close to the situation who are not connected to Google. The company has a far smaller share of the overall display ads market and it would be hard for the FTC to narrow down its market definition to a single part of the business, such as ad serving, to make a case for abuse of a dominant position, these people said. One Google rival also predicted that it was unlikely that the FTC's commissioners would back such a controversial case so soon after dropping their inquiry into Google's core search business. Google had 15 per cent of the US online display ad market last year, slightly ahead of Facebook, though the gap is set to grow wider in 2013, according to eMarketer. At the time it bought DoubleClick, four of the FTC's five commissioners backed the deal, though they said that they would "closely watch these markets and, should Google engage in unlawful tying or other anti-competitive conduct, the commission intends to act quickly." The agency has yet to approach Google about the issues it is reviewing, according to one person familiar with the case. Google had no comment late on Thursday.