Issue No. 7, May 2021

Ask an Expert: Buyers.json

SpotX works with many dedicated inventory quality experts who really know their stuff. In each issue we pick their brains to get answers on burning questions from the market – if you have a question that you’d like us to address, please email

The IAB Tech Lab recently released two new specifications, buyers.json and DemandChain Object, to bring transparency to programmatic advertising and better combat malvertising, which is when bad actors use digital ads to spread malware.

In this issue, John Murphy, Chief Strategy Officer at Confiant, answers your most-asked questions about buyers.json and the DemandChain Object.

What are the core benefits of buyers.json and DemandChain Object to the industry?
John Murphy: The main benefit is bringing buyer identity out of the shadows. That alone will change the game for malvertisers by accelerating detection and raising their cost of doing business. A large portion of malvertisers’ costs stem from getting onboarded. They have to invest in creating fake accounts backed by fake corporate entities. All of this is expensive, time consuming, and legally fraught. The investment is worth it today because each entity can be reused and kept active for a prolonged period of time. If we can reduce that time to just hours or days, the economics will no longer make sense.

Buyer identity can also serve as the foundation for advanced reputation systems that would allow companies like Confiant to provide detailed risk assessments about new buyers, helping both platforms and publishers decide who should have access to the programmatic ecosystem.

At a high level, how does it work?
JM: Buyers.json is a simple mechanism to allow demand-side platforms (DSPs) to publicly share the names and identifiers of the buyers they represent, facilitating quick identification of threat actors when attacks occur. It acts as the mirror image of sellers.json, which allows supply-side platforms (SSPs) to share the identities of the publishers they represent.

DemandChain Object is an extension object within the OpenRTB protocol that allows sellers to see all parties who are involved in the purchase of an impression. The object is composed of a set of nodes where each node represents a specific entity involved in the transaction.

These initiatives mirror previous transparency efforts on the sell side, like sellers.json and SupplyChain Object.

Along with several others, Confiant is a proponent of buyers.json and the DemandChain Object, going as far as creating Tell us more about this initiative and how it’s progressed.
JM: One of the chief challenges with eradicating malvertising is the lack of transparency into buyer identity. When buyers can remain anonymous, they can easily shift from one DSP to another, always remaining one step ahead of enforcement efforts. Publishers and SSPs seldom have insight into the true identities of buyers and therefore cannot relay the information to DSPs that would allow them to block a known bad entity across all access points at once. For instance, they might know that they got a bad ad from buyer ID 1sid23f on one DSP, but not realize that this same buyer is active on another DSP under buyer ID a938fds. It’s maddening.

The end effect is whack-a-mole, with the same entity appearing again and again across different DSPs. Buyers.json and DemandChain Object help solve this by providing full transparency into buyer identity. The exact technical details differ a lot across the two initiatives, but the underlying philosophy is that by moving buyer identity out of the shadows, we can empower the good guys in the industry and force the bad actors out of the ecosystem.

Over the past ten months, Confiant has held a series of invite-only roundtables with leading publishers and platforms to get to the root of the problem: How do we, as an industry, eradicate malvertising? We’ve used these forums to advocate on behalf of buyers.json and DemandChain Object. We’ve also been active participants in the IAB Tech Lab’s buyer-transparency working groups. To demonstrate our strong support for IAB Tech Lab’s initiatives, we created to both educate the industry and to allow companies to demonstrate their support.

Where can readers learn more about this initiative?
JM: We created to help educate the industry about buyers.json and buy-side transparency in general. It’s a great resource for learning more about these initiatives and pledging your support. The IAB Tech Lab is also a great resource. In addition to the draft specs, IAB Tech Lab developed a fantastic implementation guide that provides guidance on how the various participants in the ecosystem — buyers, DSPs, SSPs, publishers, etc. — should make use of new standards.

Q: Is there anything else we should know?
JM: Buyers.json and other buy-side transparency efforts will succeed only if publishers demand them. They have the potential to be transformative, but that potential will be realized only if we can get broad adoption by DSPs. While we strongly believe that DSPs stand to gain from buyers.json and DemandChain Object (not least by helping to eradicate bad actors who steal brand assets and masquerade as legitimate advertisers), the truth is that DSPs have concerns about revealing their client lists and devoting engineering cycles to implementation. Publishers need to make clear to SSPs and DSPs that buyer transparency is important to them and that they are willing to favor demand sources that promote transparency. Only then will DSPs devote the time and resources to these initiatives.

It’s worth emphasizing that this is not a war between the buy side and the sell side (or advertisers and publishers). It’s a war between the legitimate buyers and sellers and the threat actors who endanger the whole industry. We have an opportunity with these buy-side transparency efforts to address risks that have been present in ad tech for too long. Let’s not miss that opportunity.

More about Confiant
Confiant’s mission is to make the digital world safe for everyone. We’re a group of ad tech veterans who specialize in cybersecurity and malware prevention, and we focus on helping publishers and ad platforms take back control of the ad experience. Confiant’s technology actively detects and blocks malicious and low-quality ads. Our solutions protect the reputation, revenue, and resources of publishers and platforms by providing real-time verification of digital ads — in fact, we invented real-time creative verification. We monitor billions of ad impressions per month for our clients, which include the likes of CBSi, Gannett, and Politico, as well as many top SSPs and DSPs.

News and Opinions

Vendor Spotlight

Improving transparency in the programmatic landscape with by Primis
Nick Frizzell, VP of Inventory Quality and Planning at SpotX, spoke with Lior Shvo, Managing Director at, about why it’s time for the industry to improve transparency and commit to maintaining clean ads.txt files.

Nick Frizzell: Tell us about and how you came up with the idea.
Lior Shvo: is an initiative powered by Primis aimed at improving the state of transparency in the programmatic landscape by helping publishers regain control over their ads.txt files.

During 2019 and 2020, we saw many of our publishing partners get lost in the dark and lose control of who is really selling their inventory. Some added thousands of ads.txt lines because they didn’t understand the specs, didn’t validate new lines, and basically didn’t understand the ecosystem, thus exposing themselves and buyers to all kinds of malicious activities. Other publishers went on the defense and stopped playing ball with the programmatic industry, unwilling to add any new partners and fearing the unknown — even if it meant losing new opportunities.

We started helping our partners manually to regain control. Seeing the positive impact, we realized we can do something big for the industry. We created an automated tool that compares ads.txt files with sellers.json and provides simple and useful feedback to help publishers and buyers gain insights into who is really buying and selling inventory in any domain.

NF: What are some of the best ways buyers, sellers, and technology platforms can use the tool?
LS: The website has four different parts; each answers different needs:

  1. Analyze domain - A tool for publishers or potential buyers to search and get a complete analysis of specific domains. This analysis includes a transparency score, flags that point to common problems we saw, and actionable insights on how to fix them. We also share the complete list of the seller domains that have access to selling the inventory so publishers can see if anyone they don’t know crept in and removed unwanted sellers.
  2. Validate seller - Copy and paste ads.txt lines in bulk to analyze existing or potential vendors. This tool helps build trust between publishers and vendors, especially with new relationships.
  3. Industry highlights - We scan 116K domains and create industry benchmarks so that every publisher can see how they are doing compared to the industry. It will also help us monitor the change in the industry that we hope and believe will happen.
  4. Resources - Part of our mission is to educate. We summarized everything there is to know about ads.txt and sellers.json to make it more accessible and understandable.

NF: What are the benefits to media owners and publishers if they clean up their ads.txt files? What about buyers of media?
LS: When publishers add ads.txt lines they don’t understand, they expose their domain to spoofing. They also add layers of resellers that many times don’t add value. Too many resellers might even affect the latency, resulting in poor user experience and SEO damage. These things have a high correlation to monetization, so cleaning up your ads.txt file and making sure it is appropriately handled will improve your RPM (revenue per mille, or 1,000 impressions).

As for buyers, if brands and agencies had a better idea of where their money was going and were confident their ad spend wasn’t being wasted, spend would increase and all parties would benefit.

NF: Have you helped media owners and publishers clean up their ads.txt files already? If so, how was that process, and what were the results?
LS: Yes, we helped a few publishers over time. They saw an increase in RPM and latency was improved. There was another less measurable impact: they sleep better. Publishers that feel in control don’t fear the unknown; they feel safe. Knowing precisely what is going on in your domain just feels good.

NF: For any media owners or publishers that believe removing unknown entries in their ads.txt file might result in loss of revenue, what do you say?
LS: Daniel Kahneman, a Nobel Memorial Prize in Economic Sciences winner, coined the term “loss aversion,” which identifies the tendency to prefer avoiding losses rather than acquiring equivalent gains. Studies show that losses are twice as psychologically powerful as gains. I would recommend publishers not let loss aversion affect their decision-making process.

NF: While developing, you developed some benchmarks. Can you share those with us?
LS: Sure. We are highlighting several industry benchmarks; a few very important ones are:

  1. An average domain has 50 different sellers in its ads.txt file. Meaning, an average publisher should receive 50 separate checks every month. The reality is very different, and most publishers are unaware of many sellers that are hidden in their ads.txt file. When you analyze your domain in, you’ll see the actual number of sellers. You should ask yourself if you are familiar with all of the sellers and if you’re getting the correct number of checks and revenue every month.
  2. There are 18 (36%) sellers in an average domain that claim to be direct (claiming they are the domain owner). A domain usually has one owner, so having 18 owners is obviously impossible. This inventory misrepresentation is reflected to buyers and publishers are losing revenue.
  3. Out of 277 ads.txt lines, 73 (26%) contain non-existing seats, meaning the seller ID in these lines does not exist in the SSP’s or exchange’s sellers.json files. This high percentage demonstrates the low maintenance of ads.txt files in the industry.
  4. The IAB Tech Lab introduced sellers.json to increase trust in the supply chain. Still, the sellers.json files from 25% of exchanges and 33% of intermediaries were not reachable in their registered domain or redirect. There are many reasons — some moved to a new server, changed their name, or merged into a new company and forgot to redirect the path to the new one; some block bots on their website and forgot to exclude the sellers.json file; and some just didn’t adopt the initiative and don’t hold a sellers.json file.

NF: Where can I access, and is it free?
LS: is a domain; everyone can access it at any time.

NF: Right now, I understand that only supports ads.txt (web traffic). Do you plan on expanding support for mobile in-app and CTV environments in the future?
LS: Yes. We have many more plans for valuable features and support in the near future. The more support we get from publishers and buyers, the better we can continue developing the product and our offerings.

NF: What else do you want to tell us? LS: We created to change the industry by bringing transparency back to the top of everyone’s minds. We are open to discussions. Try us. Ask a question. Share a thought. Give feedback. We would be happy to hear from you.

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