Ad Supply Chain
The ad supply chain is the chain of intermediaries an ad passes through between the advertiser who pays and the publisher page where it appears.
The ad supply chain is the full sequence of companies and technology platforms an ad passes through between the advertiser who pays for it and the publisher page where it finally appears. Each link in the chain, demand-side platforms, ad exchanges, supply-side platforms, and resellers, handles part of the buying, selling, or delivery, and most take a cut along the way.
How it works#
In a typical programmatic transaction, an advertiser's budget flows through a Demand-Side Platform (DSP) into an Ad Exchange, which connects to a Supply-Side Platform (SSP) representing the publisher. Inventory can also be resold one or more times before reaching the page, lengthening the chain. The SupplyChain Object (schain) records each hop so buyers can audit the route.
Why it matters#
Longer chains mean more fees and more places for fraud or misrepresented inventory to hide. That is why buyers practice Supply Path Optimization (SPO) to find the shortest, cleanest route to the same impression. For competitive researchers, tracing the chain reveals which networks and resellers actually deliver an advertiser's ads. OpenAdLibrary's Click-Trace follows the delivery path from creative to landing page, exposing how native demand is routed in practice.
Related terms: SupplyChain Object (schain), Supply-Side Platform (SSP), and Supply Path Optimization (SPO).
