Google Inc. and Yahoo Inc. told the Justice Department about a two-week test combining some of their search and advertising business before it happened, the two companies said on Wednesday.
"We informed the Justice Department before we launched this test and we have been responsive to their questions about it," Google spokesman Adam Kovacevich said.
Yahoo said separately that it also spoke to antitrust regulators. "Yahoo proactively kept the Department of Justice informed of its intentions to conduct this limited test with Google and have provided information to DOJ on the nature of the test," Yahoo spokeswoman Tracy Schmaler said.
A source, who spoke on condition of anonymity, said earlier that the government had been concerned about collaboration between the two companies, who lead the market in Internet searches.