This page aggregates measured, corroborated evidence: donors' iPhones recorded apps contacting this domain, every claim below was reported by separate accepted donations and published under a human verdict (later rows for an approved app inherit its verdict). A contact is a measurement, not an accusation — it does not show what data was sent.
prebid-server.rubiconproject.com
classified as advertising · 2
What our research panel found AI-drafted · human-reviewed
We ask several independent AI models the same question and publish their answers separately — cross-vendor agreement is evidence against fabrication, and disagreement is worth seeing. 3 of 3 models answered, overall confidence high. A human reviewed this domain's claims before anything here published.
Anthropic Claude — advertising
rubiconproject.com is the ad-exchange/SSP domain historically operated by The Rubicon Project (now Magnite), and the 'prebid-server' host is header-bidding/real-time-bidding infrastructure, which normally involves sending device, IP, and ad-request data to a third party. Since the app's label declares no collection or sharing at all, this contact appears to imply a data flow the label does not cover; a reviewer should confirm the label field is genuinely empty rather than simply unavailable.
OpenAI — advertising
prebid-server.rubiconproject.com is associated with Rubicon Project's programmatic advertising infrastructure. The app declares no data collection or sharing, so this advertising-related contact appears undisclosed.
Google Gemini — advertising
prebid-server.rubiconproject.com is operated by Rubicon Project (Magnite), an advertising exchange and header-bidding platform. Contacting this domain appears undisclosed because the app declares collecting and sharing no data.
Apps measured contacting this domain
| App | Label gap | Donations | Contacts | Seen |
|---|---|---|---|---|
| Speedtest by Ookla | not in label | 4 | 13 | 2026-07-28 → 2026-07-29 |
The corpus grows one report at a time: donate your App Privacy Report — anonymous by design.
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