The players
219 companies and organisations that make up ad tech, what each one does in plain English, and where it sits in the chain.
All categoriesWalled gardens & platforms 20DSPs (buy side) 40SSPs (sell side) 32Ad exchanges 8Ad servers 15Header bidding & wrappers 7CTV & video 30Mobile app monetisation 15Attribution & MMPs 8Verification 19IVT & fraud prevention 21Brand safety & ad quality 13Data & CDPs 20Identity 10Clean rooms 6Consent & privacy 8Retail & commerce media 19Native & recommendation 11Creative & DCO 9Agencies & holding companies 11Digital out-of-home 8Audio & podcasts 5Affiliate & performance 9Workflow & ad ops 7Industry bodies 12
Broadsign
PrivateSoftware that runs many of the world's digital billboards, now including the Place Exchange SSP.
Digital out-of-homeCanadaClear Channel Outdoor
CCO +2.3%Major US billboard and airport advertising company, agreed to be taken private by Mubadala.
Digital out-of-homeUSAHivestack
AcquiredProgrammatic DOOH platform acquired by Perion in 2024.
Digital out-of-homeCanadaJCDecaux
DEC -0.1%The largest outdoor advertising company in the world: bus shelters, airports and billboards.
Digital out-of-homeFranceOutfront Media
OUT -0.2%US billboard and transit advertising company, including New York subway screens.
Digital out-of-homeUSAPlace Exchange
AcquiredIndependent out-of-home SSP, acquired by Broadsign in 2025.
Digital out-of-homeUSAStröer
SAX +2.0%Germany's leading out-of-home advertising company, also owning t-online.
Digital out-of-homeGermanyVistar Media
AcquiredLeading programmatic digital out-of-home platform, bought by T-Mobile in 2025.
Digital out-of-homeUSA