Canada's Competition Bureau has filed a lawsuit against Google for its alleged anti-competitive behavior in the ad tech sector, demanding the sale of DoubleClick for Publishers and AdX. The Bureau asserts that Google holds a dominant market share of 90% in publisher ad servers and has unlawfully tied its services to stifle competition. Google plans to contest the allegations, arguing that the online advertising market is competitive. This legal action is part of a broader trend of scrutiny facing Google, including actions from U.S. regulators and European courts.