See which Supply-Side Platforms (SSPs) hold the greatest number of direct relationships with top mobile publishers, as determined by North American traffic quality. Pixalate’s July 2025 SSP Rankings: ‘Direct’ Access to Top 100 Mobile Apps reports analyze app-ads.txt listings from the top 100 mobile app publishers on the Publisher Trust Index (PTI), ranking SSPs by their direct-seller presence across high-quality ad inventory sources. Leading SSPs featured include Verve, Magnite, Criteo, PubMatic, InMobi, and more.
Pixalate’s data science team compiles the SSP Rankings: ‘Direct’ Access to Top 100 Mobile Apps reports by analyzing app-ads.txt files from the top 100 mobile app publishers featured in the Publisher Trust Index (PTI). Analyses consist of 500+ mobile app sellers.
For the purposes of this report, the ‘Top 100 Mobile Apps’ refers to mobile apps that rank in the top 100 on Pixalate’s regional and platform-specific Publisher Trust Indexes (PTI).
The PTI evaluates mobile apps based on a combination of traffic quality metrics, including invalid traffic (IVT) rates, viewability, brand safety, and more. Apps ranked at the top of the PTI represent high-quality, brand-safe environments and are widely recognized as premium inventory in the open programmatic advertising ecosystem.
Direct seller inventory refers to ad inventory sold through a supply-side platform (SSP) or exchange with which the publisher has a direct business relationship. In app-ads.txt, entries marked as “DIRECT” indicate that the publisher has authorized that platform or exchange to sell their inventory directly, without intermediaries.
Reseller inventory refers to ad inventory sold through an intermediary. In app-ads.txt, entries marked as “RESELLER” indicate that the publisher has authorized another party (such as an ad network or SSP partner) to resell their inventory. Compared to direct relationships, reseller paths can reduce transparency and control.
For this report, Supply-Side Platforms (SSPs) are ranked by the proportion of app-ads.txt listings from the top 100 apps in Pixalate’s Publisher Trust Index (PTI) that authorize the SSP as a direct seller. The metric is calculated using this formula:
= (Num. of app-ads.txt files among the top 100 apps that list the SSP as a direct seller ÷ Top 100 apps) × 100%
This reflects an SSP’s presence across high quality mobile app inventory. It does not measure impression volume, but instead indicates how frequently an SSP is directly listed to sell inventory within the highest-ranked environments.
For a qualitative analysis of sellers, see Pixalate’s Seller Trust Index.
Pixalate is a global platform for privacy compliance, ad fraud prevention, and data intelligence in the digital ad supply chain. Founded in 2012, Pixalate’s platform is trusted by regulators, data researchers, advertisers, publishers, ad tech platforms, and financial analysts across the Connected TV (CTV), mobile app, and website ecosystems. Pixalate is MRC-accredited for the detection and filtration of Sophisticated Invalid Traffic (SIVT).
Disclaimer: The content of this page reflects Pixalate’s opinions with respect to the factors that Pixalate believes can be useful to the digital media industry. Any proprietary data shared is grounded in Pixalate’s proprietary technology and analytics, which Pixalate is continuously evaluating and updating. Any references to outside sources should not be construed as endorsements. Pixalate’s opinions are just that - opinion, not facts or guarantees.
Per the MRC, “'Fraud' is not intended to represent fraud as defined in various laws, statutes and ordinances or as conventionally used in U.S. Court or other legal proceedings, but rather a custom definition strictly for advertising measurement purposes. Also per the MRC, “‘Invalid Traffic’ is defined generally as traffic that does not meet certain ad serving quality or completeness criteria, or otherwise does not represent legitimate ad traffic that should be included in measurement counts. Among the reasons why ad traffic may be deemed invalid is it is a result of non-human traffic (spiders, bots, etc.), or activity designed to produce fraudulent traffic.”
