In the UK, people spend a third of their time online using sites owned by either Google (such as YouTube) or Facebook (such as Instagram), rendering attention on these platforms extremely valuable to advertisers.
According to the watchdog’s interim report [PDF], Google accounted for more than 90 per cent (£6bn) of all UK revenue earned from search advertising in the UK in 2018. Meanwhile, Facebook accounted for almost half (more than £2bn) of display advertising revenue.
Google paid approximately £1bn to be installed as the search engine on mobile services, with the “vast majority” of payments going towards Apple. The companies also strengthened their dominance through greater access to market data (such as through new search queries to train algorithms) and personal data collection for ad targeting, with most people being forced to “share considerable amounts of personal data as a condition for using the service” and privacy settings being made difficult...