Generative Engine Marketing (GEM) is the practice of making your business a source that AI answer engines (ChatGPT, Perplexity, Gemini, Copilot and Google's AI Overviews) name and cite when a buyer asks a question. It covers what others call generative engine optimization (GEO), answer engine optimization (AEO) and LLM optimization (LLMO), plus the off-site brand work and measurement around them.
This guide is written for small and mid-sized businesses. It covers the terminology, the verified size of the shift, how answer engines choose sources, a reality check on llms.txt and AI crawlers, the local angle, a prioritised checklist and how to measure progress. At Scalehackerlab this work is sold as SEO & AI search; the guide uses the industry labels because they are the terms people search for.
GEO, AEO, LLMO, AI SEO and GEM: what is the difference?
They are overlapping labels for the same job: being included and cited in AI-generated answers. SEO is the parent discipline. GEO was coined in a 2023 research paper led by Princeton; AEO is older and comes from the featured-snippet and voice-search era; LLMO and AI SEO are vendor jargon with no canonical origin. GEM is our house term, not an industry standard, which is why we define it every time we use it.
| Term | One-line meaning | Who uses it |
|---|---|---|
| GEO (generative engine optimization) | Optimizing content so generative engines include and cite it | Academic researchers and most SEO tool vendors; the most widely used label |
| AEO (answer engine optimization) | Optimizing to be the direct answer in snippets, voice assistants and AI chat | SEO practitioners since the featured-snippet era |
| LLMO (large language model optimization) | Improving how language models represent and mention a brand, in training data and in live retrieval | Some SEO vendors and consultants; industry jargon |
| AI SEO | Ambiguous: SEO for AI search surfaces, or using AI tools to do SEO | Agencies and tool marketing; always ask which sense is meant |
| GEM (Generative Engine Marketing) | GEO and AEO on-site work plus off-site brand mentions, reviews, PR and AI-visibility measurement | Scalehackerlab's umbrella term |
If a vendor pitches you any of the five, ask what work is included. Our glossary defines the related terms (query fan-out, grounding, zero-click search) in one place.
How big is the shift to AI search?
Big enough to plan around, and different from the headline version: people still search Google in enormous volume, but far fewer of those searches end in a click. At I/O 2026 Google said AI Overviews has more than 2.5 billion monthly active users and AI Mode more than 1 billion (2026). Those are company-reported figures, and an AI Overviews "user" was shown the feature rather than choosing it.
What happens to clicks when an AI answer appears:
- Fewer clicks on results. Tracking 68,879 real Google searches by 900 US adults in March 2025, Pew Research Center (2025) found users clicked a traditional result on 8% of visits to pages with an AI summary, against 15% without one. They clicked a link inside the summary on just 1% of visits. Google disputed the methodology.
- The top spot is worth less. Across 300,000 keywords, the presence of an AI Overview correlates with a 58% lower click-through rate for the top-ranking page, according to Ahrefs' December 2025 data (published 2026). It is a correlation, not proof of cause.
- Most searches end on Google. 68.01% of US Google searches ended without a click in the first four months of 2026, up from 60.45% in 2024, according to SparkToro's analysis of Similarweb data (2026).
What buyers are doing instead:
- B2B research starts in a chatbot. 51% of B2B software buyers start their research with an AI chatbot more often than with Google, up from 29% eleven months earlier, according to G2's Answer Economy report (2026; survey of 1,076 decision-makers). Caveats: self-reported, and G2 is a review marketplace with an interest in the result.
- AI referrals are still a small share of visits. Across 1,215 US enterprise domains in 10 industries, AI assistants sent 1.08% of all website traffic between May and September 2025, and 87.4% of that came from ChatGPT, according to Conductor (2026). Enterprise sites only, and a 2025 window; the share has grown since, but plan for AI search as a credibility and conversion channel before it is a volume channel.
- AI referrals are growing and, in retail, convert well. Adobe Analytics data reported by TechCrunch (2026) shows AI traffic to US retail sites up 393% year over year in Q1 2026, converting 42% better than non-AI traffic in March 2026 after converting 38% worse a year earlier. This is US retail only, and the baseline is all non-AI traffic, not Google organic; do not assume the same lift for a B2B services firm.
One number to retire: in February 2024 Gartner predicted that traditional search engine volume would drop 25% by 2026. That is not what happened. One year after AI Overviews launched, BrightEdge (2025) reported Google search impressions up 49% with click-through rates down nearly 30%, and Google says (2025) total organic click volume has been "relatively stable", though it published no data.
How do answer engines choose what to cite?
Answer engines retrieve pages from a search index, pull out the passages that resolve the question, and generate a response that cites some of them. No engine publishes its selection formula, so the honest answer is built from one peer-reviewed experiment, several large correlation studies and the official guidance from Google and Microsoft.
Citing sources, quotations and statistics (lab evidence). In the GEO paper, presented at KDD 2024 by researchers from Princeton, Georgia Tech, the Allen Institute for AI and IIT Delhi, content tactics were tested on a benchmark of 10,000 queries. The three best (citing sources, adding quotations and adding statistics) produced a relative visibility improvement of 30–40%, and the authors conclude that "GEO can boost visibility by up to 40% in generative engine responses." Keyword stuffing offered "little to no improvement". Lower-ranked sites gained most: citing sources raised visibility by 115.1% for sites ranked fifth, while the top-ranked site lost 30.3% on average. The caveat: this is a lab benchmark on a simulated engine plus a Perplexity test, run in 2023–24, and "visibility" means share of the answer, not traffic. Treat it as direction, not a guarantee.
Brand mentions outweigh backlinks (correlation). Studying 75,000 brands, Ahrefs (2025) found that branded web mentions correlate 0.664 with how often a brand appears in AI Overviews, against 0.218 for backlinks. It is a correlation on established sites, but the implication holds for a small company: being talked about on other sites matters more than collecting links.
Ranking first matters less every quarter. In March 2026 Ahrefs analysed 863,000 keywords and 4 million AI Overview URLs: only 37.9% of cited URLs also sat in the top 10 blocks of the same search, down from 76% in July 2025; 31.2% ranked between 11 and 100 and 31.0% did not rank in the top 100 at all. Ahrefs attributes the drop to query fan-out: Google splits the question into sub-queries and cites the pages that appear across those, so a page that answers one sub-question clearly can be cited for a query it never targeted. For a small business this is the opening: you do not have to outrank the big sites, you have to answer the specific sub-question better than they do.
Freshness helps, modestly. Across 17 million cited URLs, Ahrefs (2025) found AI assistants cite content that is 25.7% fresher than organic results, with ChatGPT showing the strongest preference and Google's AI Overviews citing slightly older pages. The average cited page was still 2.9 years old. Update the facts and show a real date; do not fake dates.
Google: no special requirements. Google's documentation on AI features says: "There are no additional requirements to appear in AI Overviews or AI Mode, nor other special optimizations necessary." A page must be indexed and eligible for a snippet. The same page explains query fan-out: both features may issue "multiple related searches across subtopics and data sources" to build a response, a technique Google described at the AI Mode launch (2025). In practice, you can be cited for a question you never targeted if your page answers one of its sub-questions clearly.
Microsoft: structure for extraction. In October 2025, Microsoft's Bing team explained that AI answers work by parsing pages into smaller pieces, and recommended descriptive headings, Q&A formats, lists and tables. Its bluntest line: "Don't hide important answers in tabs or expandable menus."
GEO vs SEO: is SEO dead?
No. GEO sits on top of SEO, because answer engines retrieve from search indexes: Google's AI features draw on Google's index, Copilot on Bing's, and ChatGPT search on pages surfaced by its own search crawler. A page that cannot be crawled and indexed cannot be cited. What changed is the goal and the metric.
| SEO | GEO / GEM | |
|---|---|---|
| Goal | Rank on a results page | Be named and cited inside the answer |
| Unit that competes | The page | The passage |
| Strongest known signals | Relevance, links, technical health | The same foundations plus sourced facts, clear structure and brand mentions |
| Main metric | Rankings, organic clicks | Mention rate in AI answers, AI referrals |
Ranking first is not a precondition: in Semrush's AI search study (2025), which covered a narrow set of digital-marketing topics, ChatGPT search cited pages ranking in positions 21 and beyond about 90% of the time. Being indexed is the precondition; being the clearest source is the differentiator.
The reality check: llms.txt, AI crawlers and citation myths
Much of the advice sold as GEO has little evidence behind it. Get four things straight before you spend a dollar.
llms.txt is optional. It is "a proposal to standardise on using an /llms.txt file to provide information to help agents use a website", published by Jeremy Howard of Answer.AI in September 2024 (llmstxt.org). In June 2025 Google's John Mueller wrote: "FWIW no AI system currently uses llms.txt." Google's AI-features documentation adds that you do not need "new machine readable files, AI text files, or markup". The data since then points the same way. Across nearly 300,000 domains, SE Ranking (November 2025) found 10.13% had the file and "no correlation between AI citations and LLMs.txt"; removing the variable from its prediction model improved its accuracy. Across 137,210 sites, Ahrefs (June 2026) found that 97% of published llms.txt files received zero requests in May 2026, and that the bots fetching the rest were mostly GPTBot and coding assistants, not AI search crawlers. We still keep one on this site because it is cheap and some agents read it; do not buy it as a ranking lever.
robots.txt: know which bot does what. OpenAI documents three agents: GPTBot collects training data, OAI-SearchBot surfaces sites in ChatGPT's search features, and ChatGPT-User fetches pages when a user asks (robots.txt rules may not apply to it). Blocking GPTBot does not remove you from ChatGPT search; blocking OAI-SearchBot does. On Google's side, Google-Extended only controls use of your content for training Gemini models, and "does not impact a site's inclusion in Google Search". AI Overviews are governed by Googlebot and the normal snippet controls. Few sites have made these choices on purpose: Cloudflare (2025) found GPTBot requests up 305% in a year while only about 14% of the top 10,000 domains had any AI-specific robots.txt rules. Also check that your CDN or firewall is not blocking AI bots by default.
Citations are volatile. In Semrush's three-month study (2025) of more than 100 million citations, Reddit went from appearing in roughly 60% of ChatGPT responses in early August 2025 to about 10% by mid-September, and Wikipedia from about 55% to under 20%. A plan built on one platform can evaporate in six weeks.
The Wikipedia and Reddit numbers are usually misquoted. You will read that Wikipedia is 47.9% of ChatGPT citations and Reddit 46.7% of Perplexity's. In Profound's study (2025) of 680 million citations, those are shares within each platform's top ten sources. As a share of all citations, Wikipedia was 7.8% of ChatGPT's and Reddit 6.6% of Perplexity's. The long tail of ordinary websites dominates, and that is where a small business competes.
What changes for local and small businesses?
For "service + city" searches the map pack still dominates; AI answers take over on informational and cost questions. In Whitespark's study (2025) of 540 manual queries, AI Overviews appeared on 68% overall, but on only 15% of pure local-intent queries, where the local pack showed 93% of the time. Informational queries triggered an AI Overview 92% of the time, and hybrid ones, such as what a service costs in a given city, 97%. It is a small, US-only study: read it as a pattern, not a precise rate.
Assistants are also far pickier than the map. ChatGPT recommended just 1.2% of more than 350,000 brand locations, against a 35.9% average appearance rate in Google's local 3-pack, and the locations it recommended averaged 4.3 stars, according to SOCi's 2026 Local Visibility Index (2026; multi-location brands, vendor study). Consumers are asking anyway: 45% used generative AI tools for local business recommendations in 2026, up from 6% a year earlier, and 40% say they trust them against 32% who do not, according to BrightLocal's Local Consumer Review Survey (2026; 1,002 US adults).
For a local business that means complete, consistent listings, reviews you earn and answer, and local informational content (costs, timelines, what to ask a provider), which is where AI answers appear and where you can be the cited source.
The GEO checklist for a small team
Work top to bottom: the first rows cost little and block everything else if they are wrong.
| Action | Why it matters | Evidence |
|---|---|---|
| Stay indexed in Google and Bing; submit your sitemap to both | Answer engines retrieve from search indexes | Google AI features doc (official) |
| Review robots.txt and firewall rules; allow OAI-SearchBot, PerplexityBot, Googlebot, Bingbot | Blocking search bots removes you from answers; blocking GPTBot only opts out of training | OpenAI bots doc (official) |
| Keep key answers in visible page text, not in tabs, images or PDFs | Engines parse pages into passages | Microsoft Bing guidance (official) |
| Open each page and section with a self-contained answer; use question headings and tables | 60% of question-form searches produced an AI summary | Pew (March 2025 data) |
| Add sourced statistics, named quotations and citations | Top three tactics in the benchmark; keyword stuffing did nothing | GEO paper (lab benchmark) |
| Refresh important pages with real updates and honest dates | AI-cited URLs are 25.7% fresher than organic results | Ahrefs (correlation) |
| Earn brand mentions: local press, trade publications, partner pages, podcasts | Mentions correlate 0.664 with AI Overview visibility; backlinks 0.218 | Ahrefs (correlation) |
| Collect and answer reviews on the platforms your category uses | ChatGPT-recommended locations average 4.3 stars | SOCi (vendor study) |
| Complete your Google Business Profile; keep name, address and phone consistent | The local pack shows on 93% of "service + city" queries | Whitespark (small study) |
| Ask the engines your top customer questions every quarter; log the answers | AI answers about businesses are often wrong | Search Engine Journal (vendor tests) |
| Add llms.txt last, if at all | Cheap, but no evidence it affects citations | Google's John Mueller (2025) |
Structured data is hygiene, not a switch: Google recommends JSON-LD markup that matches the visible text, and says no special schema is required for AI features.
This is the loop we run for subscribers as the GEM Sprint add-on on any plan, but nothing in it requires us. A disciplined owner with one marketer can work through the table in a quarter. What usually fails is follow-through, the same reason most SMB marketing is losing ground.
How do you measure generative engine marketing?
Measure three things: AI referrals in your analytics, brand mentions across the web, and how often the engines name you for your buyers' questions. Few companies do it yet: only 16% of brands systematically track AI search performance, according to McKinsey (2025).
- AI referrals. Create a channel group in your analytics for referrers such as chatgpt.com, perplexity.ai, gemini.google.com, copilot.microsoft.com and claude.ai. Expect a small share of visits, and undercounting: much AI traffic arrives without a referrer. After ChatGPT's May 2026 interface change, the homepage share of its referrals rose from roughly 26–29% to about 62–63%, according to Similarweb (2026), so your homepage has to explain the offer fast.
- What the search consoles show. Google includes AI Overviews and AI Mode traffic in Search Console's overall "Web" totals, per its documentation, so you cannot separate it. Bing Webmaster Tools added an AI Performance report in February 2026 that shows citations, cited pages and grounding queries for Copilot and Bing's AI summaries, as a sample of activity.
- Brand mentions. Count the new third-party pages, videos and podcasts that name your company each month, linked or not.
- Prompt testing. Write down the 10–20 questions that precede a purchase in your category, in a buyer's words. Ask ChatGPT, Gemini, Perplexity, Copilot and Google AI Mode on a fixed schedule. Log whether you are mentioned, what is said and which sources are cited. Answers vary from run to run, so track the trend in your mention rate, not a single result.
Review them on the same cadence as the rest of your numbers; the hidden cost of manual KPIs explains why that cadence matters. GEM works best as one loop inside a system with a single accountable owner, which is the logic behind Growth-as-a-Service.
Where to start this month
Start with the prompt test: it costs nothing and shows where you stand.
- This week: run your buyers' top questions through the engines and log who gets cited. Check robots.txt and your firewall.
- Weeks 2–3: rewrite your three highest-intent pages so each opens with a complete answer, with sourced numbers.
- Week 4: fix your Google Business Profile, listings and review replies, and pitch one piece to a trade publication or local outlet.
- Every quarter: repeat the prompt test, update the pages whose facts changed, and review AI referrals.
If you would rather see this mapped to your own company, the free growth assessment returns a strategy document in 48 hours, no credit card required. Weighing in-house against handing it over? Is Growth-as-a-Service right for you? is an honest fit check.