The new study from adtech company Ad-Shield claims to be the first to comprehensively measure and explain the scale of “dark traffic”. “Dark traffic” is defined as page views hidden to publishers by the strictest types of ad-blockers. The report claims to have found 976 million users globally representing “dark traffic” across the web, totalling 18% of all web traffic. In the UK, the report found that 23% of web traffic is “dark”, representing 16 million users. “The growth of dark traffic undermines the ability of publishers to fund the production of quality content, or even operate as a business.