The U.S. Federal Trade Commission has reportedly launched an investigation into Google's display ad business amid complaints from rivals that the company is abusing its power in how it sells online-graphical and video ads.
The examination, which has been reported in The Wall Street Journal and other news outlets, concerns a process of grouping ad-related services together known as "tying" or "bundling." Some of Google's advertising-technology rivals have complained to antitrust authorities that the company has been bundling those ad services for website publishers so that the publishers would have to use them all rather than just one Google service, reports say.
The FTC and Google both declined to comment on the reports.
The FTC examination is still in its early stages, the reports say, and may not ultimately result in a formal probe.
The reported inquiry comes just several months after Google settled a different antitrust case with the FTC over its search engine and search advertising business.
After that 19-month investigation, Google agreed to stop certain search practices such as scraping Web content from rivals and allegedly passing it off as its own.
Display advertising comprises the videos, text, images and other interactive ads appearing on the desktop and mobile devices.
In display ads, Google's DoubleClick advertising technology provides its advertising technology to publishers, agencies and other advertisers. The technology, which Google acquired in 2007, creates an auction marketplace for the trading of display ad space.
Google generates the bulk of its revenue through advertising. Google websites' advertising brought in sales of over US$31 billion in 2012; total Google revenue was over $46 billion.