Under the deal, announced June 12, Google would serve ads against some Yahoo search queries. The deal was seen as a way for Yahoo to avoid a hostile takeover by Microsoft and placate shareholders, because it was expected to goose Yahoo's fresh cash flow by $250 million to $450 million in the first year. But the companies said they would delay implementation to allow regulators to asses the deal, and it didn't take long for the Department of Justice to open a long, hard look at the search-advertising business. Additionally, Microsoft and other advertisers, through the Association of National Advertisers, came out against the deal.

Recent negotiations to limit the deal's scope did little to pacify the concerns of the types of advertisers Google is courting to use not just search but also its myriad other advertising products.

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