A judge has ruled that Google holds monopoly power in key areas of online advertising, specifically in publisher ad servers and ad exchanges. This decision is a significant blow to Google, reinforcing claims that its dominance stifles competition and harms both advertisers and publishers. The ruling could lead to major changes in how Google operates its ad business, potentially requiring the company to restructure or divest parts of its advertising technology. Google has announced plans to appeal, insisting that there is still healthy competition in the market. This ruling adds to growing regulatory pressure on Big Tech companies and highlights ongoing concerns about monopolistic practices in the digital advertising space.