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      Seller Trust Index (STI)

      Ranking all sellers, including supply-side platforms (SSP), listed in ads.txt and app-ads.txt. Trust and sustainability scores for 580+ sellers in 140+ markets, across web, mobile, and connected TV (CTV) inventory.

      In this article:

      What Is the Seller Trust Index (STI)?

      The Seller Trust Index (STI) ranks web, mobile, and connected TV (CTV) sellers based on their direct relationships with premium publishers (sustainability), authorized seller paths (via SupplyChain Object [SCO] verification), Invalid Traffic (IVT), Bundle Integrity, and country-level market share.

      It uses proprietary technology to assess seller trust and sustainability, using the SCO to provide a multidimensional view of ad transactions. The rankings are relative to peers within each country and rely solely on buy-side data to ensure impartiality.

      Pixalate analyzes 50+ billion monthly global advertising transactions to rank 580+ sellers across 140+ countries. 

      Learn about the STI’s ranking criteria.

      How Are Sellers Ranked?

      In this section:

      How Web Sellers Are Ranked

      The Web Seller Trust Index focuses on web traffic, including both mobile web and desktop inventory.

      Reports are available by quarter and by country.

      • Note: Regional reports were available prior to Q2 2024.

      Screen Shot 2024-09-13 at 9.40.16 AM

      Criteria used to rank web sellers:

      • Market Share Score
      • Supply Path Optimization (SPO) Score
      • SupplyChain Object (SCO) Verification Score
      • General Invalid Traffic (GIVT) Score
      • Sophisticated Invalid Traffic (SIVT) Score
      • Made for Advertising (MFA) Risk Score
      Learn about the STI’s ranking criteria.

      How Mobile Sellers Are Ranked

      The Mobile Seller Trust Index focuses on mobile in-app traffic across the following app stores:

      • Apple App Store (iOS)
      • Google Play (Android)

      Reports are available by quarter and by country.

      • Note: Regional reports were available prior to Q2 2024.

      Screen Shot 2024-09-13 at 9.39.56 AM

      Criteria used to rank mobile sellers:

      • Market Share Score
      • Supply Path Optimization (SPO) Score
      • SupplyChain Object (SCO) Verification Score
      • General Invalid Traffic (GIVT) Score
      • Sophisticated Invalid Traffic (SIVT) Score

      Learn about the STI’s ranking criteria.

      How Connected TV (CTV) Sellers Are Ranked

      The Connected TV (CTV) Seller Trust Index focuses on CTV traffic across the following stores:

      • Roku Channel Store
      • Samsung Smart TV
      • Amazon Fire TV
      • Apple TV tvOS App Store

      Reports are available by quarter and by country.

      • Note: Regional reports were available prior to Q2 2024

      Screen Shot 2024-09-24 at 9.55.58 AM

      Criteria used to rank CTV sellers:

      • Market Share Score
      • Supply Path Optimization (SPO) Score
      • SupplyChain Object (SCO) Verification Score
      • Bundle Integrity Score
      • Invalid Traffic (IVT) Score

      Learn about the STI’s ranking criteria.

      Ranking Criteria Definitions

      Definitions of the STI’s ranking criteria for web, mobile, and CTV sellers. Each inventory type follows its own set of criteria, so refer to the section above for specific details.

      Criteria defined in this section:

      Bundle Integrity Score

      Measures the volume of seller traffic utilizing standardized app store IDs in the bid stream.

      How to interpret Bundle Integrity Scores.

      Invalid Traffic (IVT) Score

      Indicates the share of a seller’s impressions that are designated as IVT. For the CTV Seller Trust Index, the “IVT Score” accounts for both GIVT and SIVT.

      • General Invalid Traffic (GIVT) Score: The share of a seller’s impressions that are designated as GIVT. 
      • Sophisticated Invalid Traffic (SIVT) Score: The share of a seller’s impressions that are designated as SIVT.

      How to interpret Invalid Traffic (IVT) Scores.

      Made for Advertising (MFA) Risk Score

      Indicates the level of Made For Advertising (MFA) traffic associated with a seller. MFA Risk Scores are based on two factors:

      1. The percentage of a seller's traffic classified as MFA.
      2. A seller's share of overall MFA traffic within a particular country.

      How to interpret MFA Risk Scores.

      Market Share Score

      A seller’s share of impressions within a particular country, inclusive of only IVT-free impressions.

      How to interpret Market Share Scores.

      SupplyChain Object (SCO) Verification Score

      The percentage of a seller's impressions where the seller acts as an intermediary in an unverified SCO. To verify, Pixalate analyzes each “node” of the SCO with corresponding entries in ads.txt and sellers.json. Pixalate only scores validated SCO strings.

      How to interpret SCO Verification Scores.

      Supply Path Optimization (SPO) Score

      Uses the SupplyChain Object (SCO) to verify the percentage of country-level ad impressions where the seller is identified as an unauthorized direct seller in publishers’ ads.txt or app-ads.txt files.

      How to interpret SPO Scores.

      Interpreting STI Scores

      What the STI’s scores reveal about web, mobile, and CTV sellers. How to navigate Pixalate’s ranking criteria and assess seller quality.

      In this section:

      Interpreting the Bundle Integrity Score

      The use of app store IDs helps reduce fragmentation in the CTV space and ensures greater consistency by aligning buyers and sellers with the same format. This gives buyers more confidence in the accuracy of the inventory being supplied.

      Learn more about malformed Bundle IDs.

      Interpreting the Invalid Traffic (IVT) Score

      IVT can manifest as proxy usage, app spoofing, and high-risk devices. Reducing IVT provides buyers with greater confidence that fraud has been mitigated.

      • Interpreting the General Invalid Traffic (GIVT) Score: GIVT is deterministic, with examples including datacenter IPs, bot activity, and duplicate impressions. Reducing GIVT provides buyers with increased confidence that fraud has been mitigated. 
      • Interpreting the Sophisticated Invalid Traffic (SIVT) Score: Sophisticated Invalid Traffic (SIVT) is fairly common, as valid and invalid traffic often blend together in the form of SIVT. This type of traffic can include display impression fraud, app spoofing, and high-risk devices. Reducing SIVT provides buyers with greater confidence that fraud has been mitigated.

      For a complete list of reported IVT types, please refer to this article.

      Interpreting the Made for Advertising (MFA) Risk Score

      MFA poses risks to both buyers and sellers in the programmatic ecosystem. For sellers, it can undermine inventory quality, potentially damaging their reputation. For buyers, advertising on cluttered MFA sites can decrease campaign effectiveness.

      Pixalate’s MFA Risk Scores are based on two factors: the percentage of a seller's traffic classified as MFA, and a seller's share of overall MFA traffic within a particular country. Pixalate evaluates the share of MFA traffic at both the seller and market (country) levels, ensuring the MFA Risk Score accurately reflects the risk level for sellers of all sizes.

      For more information on Pixalate's MFA solutions and background, please refer to this article.

      Interpreting the Market Share Score

      Buyers can use the Market Share Score to identify potential new partnerships at scale and identify partners who have substantial reach within markets of interest. Publishers can use it to find new sellers to collaborate with in countries of interest, expanding their supply chain to grow and acquire inventory access in new markets

      Interpreting the SupplyChain Object (SCO) Verification Score

      This SCO Verification Score assesses the authorization of each seller in the supply chain, as outlined in the SCO. If any seller in the chain is unauthorized, all sellers involved in that transaction receive a negative grade.

      This score reflects a seller's commitment to upholding industry standards established by the implementation of the SCO. It encourages them to partner with authorized sellers only, and to verify the authorization of existing partners.

      Interpreting the Supply Path Optimization (SPO) Score

      This score reflects the extent of a seller’s direct relationships with publishers, highlighting the level of optimization achieved in their supply chain. By fostering direct relationships, sellers can:

      • Reduce CPMs for buyers and enhance efficiency, minimizing the reliance on resellers and reducing transaction complexity.
      • Hit sustainability goals, defined as the reduction of hops in ad transactions and the prioritization of direct sellers listed in ads.txt and app-ads.txt.