(AP) -- Federal regulators are seeking more information about Internet search leader Google's proposed purchase of digital advertising company Admeld.
The request, disclosed late Wednesday, is the latest sign of the intensifying government scrutiny on Google as the company tries to expand its Internet empire.
The U.S. Justice Department's review of the Admeld deal marks the fourth time in the last three years that the government has taken a closer look at a Google acquisition to determine if it would drive up prices or stifle competition. After lengthy inquiries, Google won approval of a $3.2 billion purchase of online ad service DoubleClick, a $681 million acquisition of mobile ad service AdMob and a $676 million purchase of airline fare tracker ITA Software.
Google, which is based in Mountain View, Calif., hasn't disclosed Admeld's selling price since the deal was announced last month.
Admeld, headquartered in New York, works with websites to help them figure out how to make the most money from the amount of space they have available for display ads. Although short marketing messages tied to search results still account for the largest slice of Google's revenue, the company's display advertising has blossomed into a major moneymaker since the company snapped up DoubleClick.
Despite its recent inroads, Google still has a smaller share of the Internet display ad market than rivals Facebook and Yahoo Inc., according to research firm eMarketer Inc. Google's lower ranking in the display ad market could help the company persuade regulators there is enough competition to persuade them to approve the Admeld deal.
Complaints that Google has been abusing its dominance of Internet search to steer traffic to its own services and drive up online advertising prices prompted antitrust regulator in the U.S. and Europe to open wide-ranging investigations into the company's business practices.
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