by Nicola Agius for Search Engine Land Google has been accused of downplaying how much it quietly increases ad auctions. The search engine admitted at the federal antitrust trial that it “frequently” inflates ad prices by as much as 5% without telling advertisers – sometimes 10%. But marketers are calling the search engine out for being too “conservative” with these figures as they believe the real number is significantly higher. Why we care. Advertisers are becoming increasingly frustrated with Google due to long-held suspicions around ad price manipulation and a lack of transparency. Although the industry accepts the search engine has a right to set minimum…