# Researcher reports ChatGPT ad pixel can transmit cross-site identifier

_Published Sunday, September 20, 2026 at 2:08 PM EDT · Products, Security · Latest · Tier 2 — Notable_

A researcher reported that OpenAI's advertising collector sets an OpenAI-domain cookie that can be sent when advertiser sites load an OpenAI pixel. The researcher observed the identifier on requests from commercial sites and said sync tokens can associate it with an account or anonymous device subject. The report says acceptance by the collector was observed, but server-side resolution to an account was not directly observed.

## Sources

- [buchodi.com](https://www.buchodi.com/chatgpt-now-knows-what-you-do-on-other-websites-via-ad-collector/)

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Canonical: https://techandbusiness.org/newswire/MK22unYuon15lKZ-3Nnylo
Published: 2026-09-20T18:08:08.622Z
Story chronology: 2026-09-20T15:18:44.000Z
Retrieved: 2026-09-20T20:00:57.268Z
Publisher: Tech & Business (techandbusiness.org)