A report in The Wall Street Journal this afternoon cites lawyers close to three big online advertising deals -- including Microsoft's $6 billion purchase of Seattle-based aQuantive -- saying that the Federal Trade Commission is investigating them for antitrust concerns.

At least in the case of the aQuantive buy, no big shocker. When Microsoft announced the deal May 18, General Counsel Brad Smith told reporters and analysts, "The transaction is obviously subject to [Hart-Scott-Rodino] review. It's also subject to potential review outside the United States. We've been assessing that. We believe it will require a notification in Germany; at this point we don't believe it will require notification in the European Union as a whole." He added, "Acquisitions of complementary assets such as the Microsoft-aQuantive deal normally do not raise antitrust concerns."

According to the Journal story, the FTC is also reviewing Yahoo!'s purchase of Right Media. Google's purchase of DoubleClick is already being reviewed -- something Microsoft urged the government to do. In May, Microsoft was confident that its acquisition would increase competition in the online advertising market.

"Obviously, as you all know, we've consistently stated, that given the importance of this business to the future development of the Internet, we think it's very important that enforcement agencies fully study the competitive implications of acquisitions in this sector," Smith said. "... The Microsoft-aQuantive transaction will promote competition and the Google DoubleClick transaction will reduce competition, and it's really as simple as that."