Company spokesman Mark Murray said the company received "a request for information" involving its recent acquisition of VXtreme, as well as an earlier deal to buy a 10 percent stake in Progressive Networks. But he cautioned: "Just because they are reviewing [these deals] doesn't mean there are any anticompetitive issues."
Progressive Networks, which makes RealAudio and RealVideo software, also received a request for information in the case. According to Reuters news service, which first reported the Microsoft probe tonight, the Justice Department is investigating the company's $150 million investment in Apple Computer as well. Murray said he is not aware of any such investigation, and Apple could not be reached for comment.
Microsoft's business practices have come under Justice Department scrutiny before, but this one marks the first since it launched a bold acquisition and investment strategy into more consumer-driven businesses this year, including a $1 billion investment in cable television giant Comcast and a 5 percent investment in VDOnet, as well as the Apple deal. The investment strategy has come under fire by many competitors of Microsoft.
"We're looking at the proposed transactions," in video streaming, Gina Talamona of the Justice Department told Reuters.
The Progressive deal, in which Microsoft holds a minority, nonvoting interest, gives the software giant the technology and market penetration it needs to push its technology as a standard for the streaming multimedia industry, analysts said. By defining a standard, the company can neutralize competitors, they added.
Last month, the Federal Trade Commission rejected the request by three senators to reopen an independent antitrust investigation of Microsoft's business practices. The senators felt the Justice Department's ongoing antitrust investigation was proceeding too slowly.
The senators were acting on allegations that the Redmond, Washington, company was not abiding by a 1994 consent decree that blocked it from using its Windows operating system to leverage the shipment of other Microsoft software. Microsoft executives denied any such breach.
In May, NetAction, an Internet-based consumer advocacy rights group, opened a campaign to "mobilize cyberspace consumers to demand stronger enforcement of antitrust laws to prevent monopolies." It primarily targeted Microsoft.
Reuters contributed to this report.