The ads.txt (Authorized Digital Sellers) initiative, introduced by the IAB Tech Lab in 2017, has become a critical tool in combating ad fraud and ensuring transparency in programmatic advertising. However, common missteps - particularly in declaring DIRECT and RESELLER entries - have led to confusion and inefficiencies. Let's try to simplify these concepts, highlight an important saleshouse scenario, and provide clear guidance for correct implementation.
What Is Ads.txt and Why Does It Matter?
Ads.txt files are publicly accessible records where publishers declare authorized sellers of their ad inventory. By verifying these files, advertisers can ensure they're purchasing inventory from legitimate sources, protecting themselves from domain spoofing and unauthorized reselling.
The correct use of DIRECT and RESELLER fields in ads.txt is crucial for maintaining transparency:
DIRECT: Indicates the publisher directly controls the relationship with the selling platform (e.g., SSP or exchange).
RESELLER: Indicates the platform resells inventory on behalf of the publisher.
Common Pitfalls in Ads.txt Implementation
1. Mislabeling Resellers as DIRECT
Why it's wrong: A DIRECT designation should only be used when the publisher manages the account directly with the selling platform.
Impact: Misrepresentation erodes trust and creates inefficiencies in the supply chain.
2. Missing Exclusive Monetization Partner Declaration
Why it's important: When a publisher delegates all inventory management to a saleshouse, the saleshouse should be declared as MANAGERDOMAIN, reflecting its exclusive role.
3. Overlapping MANAGERDOMAIN Declarations
Why it’s problematic: Declaring multiple MANAGERDOMAIN entries for the same country causes ambiguity, leading buyers to ignore these declarations altogether.
4. Lack of OWNERDOMAIN Declaration
Why it’s needed: The field links the inventory to its legitimate owner, helping buyers distinguish between owned and resold inventory.
The Special Case: OWNERDOMAIN = Publisher, MANAGERDOMAIN = Saleshouse
In scenarios where a publisher fully delegates inventory management to a saleshouse, the saleshouse becomes the sole entity eligible for a DIRECT declaration in the ads.txt file.
How It Works
Money Flow: Ad revenue flows from the advertiser to the saleshouse, which then passes it to the publisher.
SSP Roles: All SSPs or exchanges interacting with the saleshouse must be declared as RESELLER since they do not directly manage the publisher’s inventory.
Example of Ads.txt Declaration
Let’s take the case of Example Publisher (owner of example.com) outsourcing monetization to SalesHouse Inc.:
Breakdown of Entries
- saleshouse.com: Declared as DIRECT because it exclusively manages the publisher's inventory.
- ssp1.com and ssp2.com: Declared as RESELLER because they resell inventory via the saleshouse.
Guidelines for Accurate Ads.txt Implementation
For Publishers
Understand Your Relationships:
- Use DIRECT only for platforms you directly manage.
- Use RESELLER for platforms acting as intermediaries.
Include OWNERDOMAIN and MANAGERDOMAIN Fields:
- Specify OWNERDOMAIN to affirm ownership.
- Use MANAGERDOMAIN to declare exclusive monetization partners.
Validate Regularly:
- Regularly audit your ads.txt file to ensure no unauthorized sellers are listed.
For Saleshouses
- Ensure your role as the exclusive monetization partner is reflected with the MANAGERDOMAIN designation.
- Educate publishers on the importance of aligning their ads.txt files with these principles.
For SSPs and Exchanges
- Accept RESELLER roles when working with saleshouses managing a publisher's inventory.
- Validate ads.txt and sellers.json entries to ensure consistency.
Why This Matters for the Ecosystem
Enhanced Transparency - Proper declarations clarify the supply chain for buyers, fostering trust and reducing fraud.
Supply Path Optimization (SPO) - Buyers can prioritize the most direct route to inventory, improving efficiency.
Risk Mitigation - Misleading or inaccurate ads.txt files create vulnerabilities; adhering to best practices ensures compliance and reduces risk.
Conclusion
Accurate implementation of ads.txt fields such as DIRECT, RESELLER, OWNERDOMAIN and MANAGERDOMAIN is essential for maintaining transparency and trust in programmatic advertising. Special cases like exclusive saleshouse scenarios highlight the importance of thoughtful and precise declarations. By following these best practices, publishers, saleshouses, SSPs, DSPs and buyers can work together to create a more transparent, efficient, and fraud-free advertising ecosystem. For further guidance, consult the IAB Ads.txt 1.1 Implementation Guide or contact support@iabtechlab.com.
