ISBA (the UK's advertiser-centric trade association) has released the results of a nine month study by PwC that concluded only half of what advertisers spend on digital advertising reaches publishers and that 15% of that spend – around one-third of supply chain costs – was not attributable to any service provider.  For the full results of the study, see https://www.isba.org.uk/knowledge/digital-media/programmatic-supply-chain-transparency-study.

In an industry were media spending will exceed $400 billion in 2021, tolerating such levels of waste raises serious concerns.