The Department of Justice in the US is now opening a formal investigation into the partnership between Google and Yahoo, the first and second place leaders in search. The investigation comes after the DoJ is fearing that it would reduce competition in the online advertising market.
It is currently preparing demands for information from executives at both companies and rival advertising firms. There was initially a two-week test run, but a formal investigation suggests that they have concrete concerns about the deal.
According to The Register, the DoJ would not open a "full probe" unless the firms were carrying out a full merger.