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The appearance of any big brand's ads on websites that the brand has specifically blocked is one of a brand's biggest nightmares. That could include specifically blacklisted sites—like Breitbart—or any category of generally controversial site, like sites in countries sanctioned by the government, sites featuring hardcore pornography, or sites containing pirated content.

According to an Adalytics report, the Google Search Partner Network (SPN) has allegedly been putting brands at risk of all of these undesirable placements without advertisers fully realizing the dangers. Adalytics researchers reported finding Google search ads for top brands and government agencies displaying on hundreds of undesirable websites.

Among those impacted were big brands—like Amazon, Apple, BMW, Home Depot, Lego, Meta, Microsoft, Paramount+, Samsung, and Uber—and top government entities including the US Treasury and the European Commission. Ads from nonprofits like the American Cancer Society and St. Jude Children's Research Hospital, as well as major media outlets like The Guardian, The New York Times, and The Wall Street Journal were also found on illegal or adult sites.