Five different newspapers cover your town. They all print stories about local business, but one only reads the council register, one only reads the chamber of commerce newsletter, one sends its own reporter, and two share a wire service. Getting into the council register does nothing for the paper that reads the newsletter. You need to know which door each one uses.
The map
| Engine | Where it gets pages | Its crawler | What this means for you |
|---|---|---|---|
| ChatGPT Search + browsing |
Primarily Bing's index, supplemented by OpenAI's own crawling | OAI-SearchBot (search)GPTBot (training)ChatGPT-User (live fetch) |
If you are not in Bing, you are largely invisible here regardless of your Google rankings. Bing Webmaster Tools is not optional. |
| Google AI Overviews The summary box |
Google's main index and ranking systems | Googlebot |
Standard Google SEO is the entry ticket. Google says explicitly there are no additional requirements. TIER A |
| Google AI Mode The conversational tab |
Same index, but heavy query fan-out and passage-level retrieval | Googlebot |
Same ticket, different game. Ranking #1 for the head term does not guarantee you serve any of the sub-queries. |
| Perplexity | Its own index, rebuilt in-house on Vespa in 2025, plus licensed third-party crawls | PerplexityBot |
An independent front door. You can be strong here and weak elsewhere, and vice versa. |
| Claude & Copilot | Claude uses a search partner; Copilot uses Bing | ClaudeBot, Claude-SearchBot |
Copilot inherits your Bing position. Claude is worth spot-checking because it skews toward documentation and primary sources. |
Sources: Google Search Central AI features documentation; Vercel/MERJ crawler telemetry; Perplexity engineering statements; OpenAI crawler documentation. See Appendix B.
The two-word distinction that matters most
Notice that OpenAI runs several bots, and they do different jobs. This trips up almost everyone, including people who should know better, so it is worth being precise:
- Training crawlers —
GPTBot,Google-Extended,Applebot-Extended. These gather text that may be used to train future models. Blocking them is a defensible business decision and it does not remove you from AI search results. - Search crawlers —
OAI-SearchBot,PerplexityBot,Claude-SearchBot. These gather pages to cite in answers. Blocking these removes you from those answers. - User-triggered fetchers —
ChatGPT-User. Fires when a person or an agent asks the tool to go and look at a specific page, live.
In 2023 and 2024 a great many businesses pasted a "block the AI bots" snippet into robots.txt to protect their content from training. A large share of them blocked the search bots at the same time, and then spent 2026 wondering why they never appear in ChatGPT. Go and read your robots.txt today. It takes ninety seconds and it is the highest-return ninety seconds in this book.
Where they overlap, and where they do not
Two practical points follow from the map.
The first is that Bing is now load-bearing infrastructure in a way it has not been for a decade. Not because anyone searches on Bing, but because ChatGPT and Copilot retrieve through it. Verifying your site in Bing Webmaster Tools, submitting a sitemap, and pushing updates through IndexNow costs an hour and unlocks two of the largest answer engines. TIER B
The second is that results diverge sharply between engines, and you should expect that rather than treat it as an error. The same prompt run on ChatGPT, Gemini and Perplexity will often return three substantially different shortlists. Chapter 17 covers what to do about it; for now, simply stop assuming one check is a measurement.
- Visit
yourdomain.com/robots.txtand read everyDisallowline. Confirm no search-class bot is blocked. - Search Bing for
site:yourdomain.com. If the count is far below your Google equivalent, that is your ChatGPT problem in one number. - Ask your developer, or check your server logs, for hits from
OAI-SearchBotandPerplexityBotin the last 30 days. Zero hits is a finding.
Verify your site in Bing Webmaster Tools and submit your sitemap. It is free, it takes under an hour, and for most businesses it is the difference between existing and not existing inside ChatGPT.