The FTC's request means there will be a delay in closing the transaction.
"While this means we won't be closing right away, we're confident that the FTC will conclude that the rapidly growing mobile advertising space will remain highly competitive after this deal closes," Paul Feng, group product manager for mobile advertising, said Wednesday in the company's blog.
Indeed, Google's dominance of online advertising related to search has led to heightened regulatory scrutiny from the Department of Justice, the Federal Communications Commission and the FTC. The latter agency this week handed Google what's called a "second request," which means the FTC wants more information as they continue to review the AdMob deal, Google said.
The company announced in November its plans to buy AdMob, a mobile display advertising provider based in San Mateo, Calif., for $750 million. Google from the start has said the deal wouldn't stifle competition, but would be a catalyst of new innovation and competition.
Feng said the company doesn't see any regulatory issues with the deal, because the growing mobile advertising market is highly competitive with more than a dozen ad networks.
Mobile ad spending is estimated to reach $416 million in 2009, accounting for 0.4% of all ad spending, according to eMarketer. Industry experts have said that the AdMob acquisition would likely prompt Google competitors, such as Microsoft and Yahoo, to seek similar acquisitions.
If completed, AdMob would be Google's third acquisition this year. In August, the company bought On2 Technologies, a video technology company. And in September, Google acquired reCAPTCHA, an anti-spam security company.