Shares of ailing internet pioneer Yahoo plunged more than 10 per cent Friday after Microsoft CEO Steve Ballmer reiterated that his company was not interested in reviving its takeover bid, dpa reported. Yahoo CEO Jerry Yang this week urged Microsoft to buy the company, just a day after Google said it was dropping plans for an advertising alliance with Yahoo, which would have boosted Yahoo's income by up to 400 million dollars per year. At a conference in Sydney, Ballmer said that Microsoft had moved on after Yahoo rejected its 33-dollar-per-share bid earlier this year. "We're not interested in going back and re-looking at an acquisition," Ballmer said, according to Bloomberg News. "I'm sure there are still opportunities for some kind of partnership around search." He didn't elaborate on the potential partnerships. The comments sent Yahoo shares down as much as 17 per cent, to 11.65 dollars, in Friday's trading on the Nasdaq, though they later recovered to 12.10 dollars.