Google faces competition probe over block on adverts that use people’s browsing history Britain's competition watchdog opened a formal investigation into Google’s cookie move in January 5 March 2021 • 1:22pm Google faces a deepening investigation over its decision to block adverts that use people’s browsing history after opponents of the move brought the case to Britain’s competition watchdog. Marketers for an Open Web, a group of news publishers and advertising companies, said it would write to the Competition and Markets Authority (CMA) over Google’s move to limit how advertisers can track users. On Wednesday, Google said it would no longer support advertising technology that relies on tracking people across different websites. The move sent ripples across the industry since Google’s advertising technology is used by millions of websites.