The interesting news in AI advertising this month was not another format — it was governance. OpenAI's targeting rules for ChatGPT ads became concrete, exclusion controls surfaced in the Ads Manager, and an external study put a number on how much of Google's AI Mode already carries ads. Together they show AI ad platforms growing the boring, necessary machinery of audiences and controls.
Key takeaways
- ChatGPT Ads Custom Audiences require at least 25,000 matched users; files accept up to 5 million identifiers and processing runs about 20–30 minutes.
- Usability depends on matched count, not rows uploaded — small local merchants are effectively shut out of deterministic remarketing.
- The Ads Manager was reported to add geo exclusion and first-party audience exclusion — the basics of cross-market ad governance.
- A third-party study says ads appear on close to 30% of Google AI Mode queries; treat this as a signal of fast-forming inventory, not an official coverage figure.
- AI Mode reshapes organic (GEO) and paid visibility at once, so brands need a query panel that logs both.
The 25,000-user floor, and who it excludes
PPC Land, reading OpenAI's Help Center documentation, reported that ChatGPT Ads Custom Audiences need a minimum of 25,000 matched users before an audience becomes usable. Lists accept up to 5 million identifiers, support hashed email and phone via SHA-256, and typically process in 20–30 minutes; per-ad-group audience bid multipliers range from 0.1x to 10x. Crucially, availability depends on the matched count after processing — not how many rows you uploaded.
That floor is a real strategy input. A small or local merchant with a modest CRM list will not clear 25,000 matches, which pushes deterministic remarketing out of reach and raises the value of clean, deduplicated, consented first-party data. If you are near the threshold, don't stake key budget on an audience that may not activate. Smaller markets are often better served by winning content and product visibility first — the organic side of the AI answer surface — while the list matures.
Exclusions: the governance layer arrives
Separately, Search Engine Roundtable reported that the ChatGPT Ads Manager gained the ability to exclude specific geographies and to upload a first-party customer list to avoid targeting certain people. OpenAI's public Help Center confirms the Ads Manager Beta exists but doesn't itemize every control on its basics page, so match rates, retention limits and consent boundaries still need verification.
