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.
ab.chatgpt.com
classified as first-party · 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 — first-party
ab.chatgpt.com is a subdomain of chatgpt.com, the app publisher's own domain (OpenAI), so this is first-party infrastructure; the "ab" prefix suggests A/B testing or feature-flag/experimentation, which would be first-party analytics rather than a third-party tracker. Any resulting data flow (app interactions, diagnostics) falls within the app's declared collection categories, so nothing here appears undisclosed.
OpenAI — first-party
The domain is a subdomain of chatgpt.com and most likely serves the app's first-party infrastructure. The provided privacy label already declares several relevant collection categories and sharing of device or other IDs, so the contact alone does not establish an undisclosed flow.
Google Gemini — first-party
The domain ab.chatgpt.com is a subdomain of chatgpt.com, the official domain for the ChatGPT app, making it a first-party endpoint. Because it belongs to the app developer rather than a third party, this contact does not indicate an undisclosed third-party data flow.
Apps measured contacting this domain
| App | Label gap | Donations | Contacts | Seen |
|---|---|---|---|---|
| ChatGPT | — | 7 | 517 | 2026-07-28 → 2026-07-30 |
The corpus grows one report at a time: donate your App Privacy Report — anonymous by design.
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