Schain - Supply Chain Object Module

Last edited: 2024/06/24

What are Schain and sellers.json in Prebid?

Sellers.json and SupplyChain are mechanisms designed to identify all intermediaries involved in the flow of money from the buying platform to the publisher.

Service providers that manage Prebid wrappers for multiple publishers and handle their payments must declare their intermediary status in the Supply Chain (SChain) object. According to the IAB OpenRTB SupplyChain Object Specification, SSPs are not allowed to add upstream intermediaries. Therefore, publishers or Prebid.js managed service providers are responsible for specifying the SChain information.

In complex supply chains, these mechanisms enhance transparency and help identify and prevent fraudulent or otherwise unacceptable supply sources, based on the business policies of the advertising consumer.

Learn more: IAB Tech Lab Sellers.json

How to include Schain information in Prebid Stack?

In the Old Platform

1. First, define a new ad network:

Ad network is basically a third party provider of the demand account that you are using on your inventory.
1. Go to Prebid Stack > Setup > Ad networks

If you do not see Ad networks in your interface - contact your Customer Success Manager to enable this feature for you.
2. Click on Add new .
3. You will be redirected to a page, where you have to add:
1. <Ad network name> - The name of the schain, used for your own convenience only, it will not be used outside of Yieldbird Platform.
2. <Ad network ASI> - The canonical domain name of the SSP, Exchange, Header Wrapper, etc. system that bidders connect to. This may be the operational domain of the system, if that is different than the parent corporate domain, to facilitate WHOIS and reverse IP lookups to establish clear ownership of the delegate system. This should be the same value as used to identify sellers in an ads.txt file if one exists.
4. Click Save
2. Add Domain SIDs
1. Go to Prebid Stack > Inventory > Domains > the domain you want to edit > Ad networks SID
2. Input the SID of the given Domain (as provided by the ad network)
3. Add Bidders that belong to a third party:

When adding or editing bidder in Own bidders select the ad network it belongs to by changing the <Relationship> from Direct to Ad Network, and specifying which ad network this bidder belongs to. Remember to fill in <Bidder SID>.

In the New Platform

1. First, define a new supply chain:
1. Go to Global setup > Schain and click Add new.
2. You will be redirected to a view where you can create a new schain. Input Supply chain name, ASI and Default Domain SID and click Save.
1. <Supply chain name> - The name of the schain, used for your own convenience only, it will not be used outside of Yieldbird Platform.
2. <ASI> - The canonical domain name of the SSP, Exchange, Header Wrapper, etc. system that bidders connect to. This may be the operational domain of the system, if that is different than the parent corporate domain, to facilitate WHOIS and reverse IP lookups to establish clear ownership of the delegate system. This should be the same value as used to identify sellers in an ads.txt file if one exists.
3. <Default Domain SID> - The identifier associated with the seller or reseller account within the advertising system. This must contain the same value used in transactions (i.e. OpenRTB bid requests) in the field specified by the SSP/exchange.
2. Optionally customize Domain SIDs for particular Domains.

Sometimes, the schain will require different SIDs for each Domain, to properly identify the flow of money. In order to do that, you will need to update SIDs on the Domain level.
1. Go to Global setup > Schain. In the overview table click on the schain where you want to update Domain SIDs (you can also click on Actions > Edit)
2. Go to Domain SIDs tab
3. Here you can add specific domain SIDs for this particular schain. If the Custom Domain SID field is left blank, it means that the default Domain SID is applied.
4. After editing click Save.
3. Add Bidders or Amazon UAM / TAM account that belongs to a third party.

After creating a schain, to make it operational you have to add Third party provider bidders to the schain.


Learn more: Adding Third party provider bidders

On this page:

• Schain - Supply Chain Object Module
• What are Schain and sellers.json in Prebid?
• How to include Schain information in Prebid Stack?
• In the Old Platform
• In the New Platform