"It's going to be a harsh winter for the No. 2 of search. Fears of a lengthy legal battle killed the controversial Google-Yahoo ad deal Wednesday, announced Google Senior VP David Drummond.

“After four months of review, including discussions of various possible changes to the agreement, it's clear that government regulators and some advertisers continue to have concerns about the agreement,” wrote Drummond on the company’s Public Policy Blog. “Pressing ahead risked not only a protracted legal battle but also damage to relationships with valued partners. That wouldn't have been in the long term interests of Google or our users, so we have decided to end the agreement.”

The deal would have allowed Yahoo’s advertising network to use ad content sourced from Google’s competing AdSense network, and generally speaking, was met with a warm reception on its announcement. A number of Google’s competitors objected, however, citing concerns that such a program would give the internet giant a whopping 80 percent of the search ad market – a position clearly prone to abuse.