Justice Examining Google-Yahoo! 'Test'

SAN FRANCISCO - The Justice Department is reportedly looking into antitrust implications of Yahoo!'s(YHOO Quote) decision to outsource some of its online ads in the U.S. to Google(GOOG Quote).

The Justice Department is concerned that a two-week test run that Yahoo! initiated with Google may violate antitrust law, according to Reuters.

The test run is part of Yahoo!'s attempt to find a strategic alternative to an unsolicited takeover bid by Microsoft(MSFT Quote).

An unnamed source told Reuters that the government is particularly concerned about a phone call from Google's Chief Executive Eric Schmidt to Yahoo's CEO Jerry Yang, in which he offered his help in dodging a Microsoft merger.

Antitrust concerns about a relationship between Google and Yahoo! have existed ever since rumors about the possibility came to the surface. Many observers have maintained that a deal between the two wouldn't fly because of Google's dominance in the search market.

Yahoo! has been scrambling to find alternatives to the Microsoft merger, including engaging in talks with Time Warner's(TWX Quote) AOL division as well as News Corp.(NWS Quote).

Shares of Yahoo! closed Wednesday down 46 cents, or 1.6%, to $28.08.