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# OpenAI signs Magnite, PubMatic to fill unsold ChatGPT ad space
- URL: https://www.medianexis.com/openai-signs-magnite-pubmatic-to-fill-unsold-chatgpt-ad-space/
- Published: 2026-11-03T15:29:29.000Z
- Updated: 2026-11-03T15:29:30.000Z
- Description: AdExchanger reports that Magnite and PubMatic have signed deals to fill unused ChatGPT ad inventory, joining a growing roster of OpenAI ad-tech partners that includes LiveRamp, Criteo, StackAdapt and Amazon Ads.
- Author: The Signals Desk
- Tags: Ad-tech, AdExchanger: OpenAI openness, prediction markets on endorsements

**Why it matters.** Ad-tech vendors gain early access to ChatGPT inventory now, but history with YouTube, Facebook Atlas and Amazon Prime’s DSP program shows platforms typically cut off third-party access once their own ad stack matures.

*Signal from* [*adexchanger.com*](https://adexchanger.com/?ref=medianexis.com) *·* [*read the original*](https://www.adexchanger.com/daily-news-roundup/tuesday-03112026/?ref=medianexis.com)*.*