Sellers.json is a file used in the digital advertising ecosystem to increase transparency by identifying the entities involved in the selling of digital advertising inventory. It is part of the OpenRTB (Open Real-Time Bidding) protocol and is maintained by the IAB Tech Lab. The file is typically hosted on a publisher's or supply-side platform's (SSP) domain and provides a publicly accessible list of authorized sellers.
Key Details of Sellers.json:
1. Purpose:
Transparency: It helps buyers (advertisers, demand-side platforms, or agencies) verify the legitimacy of sellers and intermediaries in the programmatic advertising supply chain.
Fraud Prevention: By listing authorized sellers, it reduces the risk of fraudulent inventory being sold.
2. Structure:
The sellers.json file is a JSON-formatted file that contains an array of seller objects. Each object represents a seller or intermediary and includes the following fields:
seller_id: A unique identifier for the seller (e.g., a publisher or SSP).
name: The name of the seller.
domain: The domain of the seller's website.
seller_type: Indicates the type of seller:
PUBLISHER: Direct seller of inventory.INTERMEDIARY: An entity that resells inventory (e.g., an SSP or ad network).BOTH: Acts as both a publisher and an intermediary.
is_confidential: A boolean indicating whether the seller's identity is confidential.
3. Example of a Sellers.json File:
{
"sellers": [
{
"seller_id": "12345",
"name": "Example Publisher",
"domain": "example.com",
"seller_type": "PUBLISHER",
"is_confidential": false
},
{
"seller_id": "67890",
"name": "Example SSP",
"domain": "examplessp.com",
"seller_type": "INTERMEDIARY",
"is_confidential": false
}
]
}4. Hosting Requirements:
The file must be hosted at the root domain of the seller's website (e.g.,
https://example.com/sellers.json).It should be publicly accessible and updated regularly to reflect any changes in authorized sellers.
5. AdX and Google's Requirements:
Google AdX (Ad Exchange) requires publishers and SSPs to provide a
sellers.jsonfile to ensure transparency in programmatic transactions.Google also provides a tool called Ads.txt (Authorized Digital Sellers) that works alongside
sellers.jsonto further validate sellers.
6. Relationship with Ads.txt:
While
ads.txtlists authorized sellers for a specific publisher,sellers.jsonprovides a broader view of all sellers and intermediaries involved in the supply chain.Together, these files help buyers verify the legitimacy of inventory and reduce ad fraud.
7. Challenges:
Accuracy: The file must be kept up-to-date to reflect current sellers and intermediaries.
Adoption: Not all publishers and SSPs have fully adopted
sellers.json, which can limit its effectiveness.
8. Benefits:
Trust: Builds trust between buyers and sellers in the programmatic ecosystem.
Efficiency: Streamlines the process of verifying sellers, reducing manual checks.
Conclusion:
Sellers.json is a critical tool for improving transparency and reducing fraud in digital advertising. By providing a clear list of authorized sellers, it helps buyers make informed decisions and ensures a healthier programmatic ecosystem. Publishers, SSPs, and other intermediaries should ensure their sellers.json files are accurate, up-to-date, and publicly accessible.