Yahoo (YHOO) moves back to the deal market as its controversial advertising partnership with Google (GOOG) is now dead.

As Fortune’s Legal Pad blogger Roger Parloff outlined last month, the legal footing was never very solid as the No.1 and No.2 Internet advertisers explored plans to work together on search advertising efforts.

The plan was first introduced in June as Yahoo was trying to fend off an unsolicited takeover bid from Microsoft (MSFT). Yahoo stubbornly resisted Microsoft’s early offers, including a $33-a-share bid in May. Microsoft then walked away and in July, activist investors like Carl Icahn started pushing for a shakeup of the Yahoo board and a more deal-friendly line up.

Yahoo shares, which had fallen to a five-year low of $11.25 last month, surge up 9% on Wednesday after news that the Google partnership was killed.

Investors apparently like Yahoo’s options a lot better without the antitrust battle that seemed to be looming with its Google ad plan. Microsoft and Time Warner’s (TWX) AOL unit – Time Warner is the parent of Fortune and CNNMoney – are among the potential deal partners.

On a conference call with analysts, Time Warner executives said that the news was positive for AOL. “The opportunity remains open for this business to rebuild itself,” the executives said.