Google Inc. (Nasdaq:GOOG) is in the crosshairs of U.S. federal regulators regarding the way it herds websites toward using online display advertising products through DoubleClick, the company’s New York-based subsidiary.

The Federal Trade Commission is only in a preliminary stage of a probe, which may not result in a formal investigation, according to different news reports. The development comes just months after the Mountain View, Calif.-based Internet search company barely dodged a U.S. antitrust lawsuit following a two-year investigation into the company’s dominant position in U.S. search advertising; the company raked in nearly 75 percent of all U.S. online ad revenue in 2012, according to research firm eMarketer.

Competitors in the market for online advertising platforms, including Seattle software giant Microsoft Corporation (Nasdaq:MSFT) and San Francisco-based Yelp Inc. (NYSE:YELP), which connects Internet users with local businesses, have complained about the way Google offers it DoubleClick Ad Exchange ad marketplace and DoubleClick for Publishers, which allows web publishers a way to monitor ad performance.

While these products don’t affect Internet end-users, they are powerful revenue-generating tools for content providers.

The FTC heavily scrutinized Google’s $3.1 billion acquisition of DoubleClick in 2007, but ultimately concluded that the purchase wouldn’t “substantially lessen competition.”

Last year, Google voluntarily adjusted the way it manages its search business in an attempt to allay concerns by consumer rights advocates and regulators, but Microsoft wasn’t impressed with the move.

“Hopefully, Google will wake up … with a resolution to change its ways and start to conform with the antitrust laws,” wrote Microsoft’s top lawyer Dave Heimer back in January. “If not, then 2013 hopefully will be the year when antitrust enforcers display the resolve that Google continues to lack.” Meanwhile, up in Canada regulators announced last week they’re preparing their own antitrust investigation.