{"page":"/blog/header-bidding-explained","modified":"2026-11-10","license":"https://creativecommons.org/licenses/by/4.0/","columns":["Question","Prebid (browser or server)","Amazon TAM and UAM","Google Open Bidding"],"rows":[["Where the auction runs","Browser or Prebid Server, before the ad server","Amazon's servers, before the ad server","Inside Google Ad Manager"],["Code on the page","Prebid.js and its adapters","APS tag","Existing Google tag only"],["Contracts","Publisher with each SSP","TAM: publisher with each buyer; UAM: through Amazon","Publisher with each exchange, plus a Google addendum"],["Who pays the publisher","Each SSP","Amazon, one payment","Google, net of its revenue share"],["Bid-level visibility","Full, in the publisher's own analytics","Auction-level records (TAM)","Google Ad Manager reporting"]],"sourceUrls":[[],[],[],[],[]]}