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FogTrail Team·

How to Get Your Startup Into the LLM Retrieval Set

Getting into the LLM retrieval set, the 5-to-10 documents an AI search engine actually considers when generating an answer, requires three concrete strategies: parasitic SEO (getting your brand mentioned on the high-authority domains that LLMs already trust), long-tail sub-query ownership (becoming the definitive source on narrow queries that larger competitors haven't bothered to cover), and entity creation (coining a term or framework that makes you the canonical source by definition). None of these require high domain authority. A Writesonic study of 2.4 million domains found that nearly 90% of ChatGPT citations come from URLs ranked position 21 or lower in traditional Google search, and separate research shows 28.3% of ChatGPT's most-cited pages have zero organic visibility in Google at all.

The retrieval set is the bottleneck. Everything else, content quality, structural optimization, freshness signals, only matters if your content survives the retrieval filter in the first place. For startups with new domains and no established authority, the path in looks different than it does for Fortune 500 brands. It's narrower, but it's real.

Why the retrieval set is the only thing that matters

The mechanics behind LLM citation follow a predictable pipeline: an AI search engine decomposes a user's query into sub-queries, runs each sub-query against a search index, reranks the results, and extracts the top-scoring passages for citation. The retrieval set, typically 5 to 10 documents per sub-query, is the total universe of content the model can cite. Everything outside it is invisible.

There is no page 2. There is no "close but not quite." If your content doesn't make the retrieval set, the LLM doesn't know it exists when generating its answer. For startups, this creates both a problem and an opportunity. The problem is obvious: new domains with limited backlinks and minimal third-party mentions start at a structural disadvantage against established players. The opportunity is subtler. LLMs don't rank content the same way Google does. Domain authority matters, but it isn't the only gate. Research from SE Ranking analyzing 2.3 million pages found that while domain traffic is the strongest single predictor of citation (SHAP value of 0.63), content depth and specificity can overcome authority gaps, especially on engines with lower authority thresholds like Perplexity and Grok.

This means startups don't need to outrank Forbes on Google. They need to outmaneuver Forbes on the specific sub-queries that LLMs generate, and they need third-party signals that make their content credible enough to survive the reranking filter.

Strategy 1: Parasitic SEO, or getting mentioned where LLMs already look

The term "parasitic SEO" sounds unsavory, but the mechanism is straightforward: if you can't get LLMs to pull from your domain directly, get your brand mentioned on domains they already trust.

The data makes the case clearly. A Writesonic study analyzing 2.4 million domains across 9 AI platforms between May and October 2025 found that the top 10 most-cited domains are almost entirely third-party platforms:

RankDomainCitationsPlatforms Citing It
1reddit.com7,328,2677 of 9
2wikipedia.org4,289,5478 of 9
3youtube.com2,661,0567 of 9
4google.com1,652,6108 of 9
5linkedin.com1,424,1348 of 9
6g2.com1,219,7268 of 9
7medium.com1,157,8818 of 9
8forbes.com1,155,9817 of 9

G2 at position 6 is especially notable. A software review site, not a media company or social platform, earns over 1.2 million citations across 8 AI platforms. For any B2B startup, a verified G2 profile isn't just a sales tool. It's a retrieval set entry point.

A Goodie study of 5.7 million citations found that 74% of the most-cited domains in LLMs are susceptible to marketing influence, meaning they're platforms where you can get your brand mentioned through legitimate participation: posting on Reddit, publishing on Medium, maintaining a LinkedIn presence, getting listed on review sites, creating YouTube content.

What parasitic SEO looks like in practice

The practical version of this isn't gaming or manipulation. It's distribution. Semrush documented a case study where they increased their AI share of voice from 13% to 32% within a single month using a deliberate cross-platform strategy: publishing cite-worthy content on their own domain, then distributing across partner sites, YouTube, G2, Reddit, and LinkedIn with consistent messaging.

The mechanism behind this is measurable. SE Ranking found that domains with profiles on Trustpilot, G2, Capterra, and Yelp have 3x higher chances of being cited by ChatGPT. Domains mentioned on 4 or more external platforms are 2.8x more likely to appear in ChatGPT responses. And the compounding effect is dramatic: domains cited across 5 to 8 AI platforms receive 182x more total citations than domains cited by only a single platform.

For a startup executing this strategy, the priority order is:

  1. G2 and Capterra listings. Low effort, high signal. A verified profile with even a handful of genuine reviews enters the retrieval set for product comparison queries across most engines.
  2. Reddit participation. Reddit is the single most-cited platform across AI search engines, with 7.3 million citations in the Writesonic study. Domains with 35,000 or more Reddit mentions earn 5.5 citations per query on average. But this requires genuine participation, not promotional posting. Reddit communities detect and downvote self-promotion immediately, and downvoted content signals low quality to AI retrieval systems.
  3. Independent comparison articles. Getting your product mentioned in third-party comparison posts (the "best X tools" articles that AI engines cite heavily for product queries) is highly effective. As of February 2026, 43.8% of cited page types in AI search are "best X" listicles.
  4. LinkedIn and Medium content. Both platforms earn over 1 million citations across AI engines. Publishing substantive content (not promotional posts) on these platforms creates additional retrieval entry points that reinforce your brand's presence in the AI search ecosystem.

The goal isn't to be on every platform. It's to be consistently mentioned across the platforms that AI engines already treat as trusted sources.

Strategy 2: Long-tail sub-query ownership

When an LLM receives a query like "what's the best way to optimize for AI search engines," it doesn't search for that exact phrase. It decomposes the query into sub-queries, each targeting a different facet: "AI search optimization tools," "how to get cited by ChatGPT," "AEO vs SEO differences," "AI search ranking factors." Each sub-query runs against the search index independently, and the results get merged.

This decomposition is the gap that startups can exploit. Large competitors own the broad queries. HubSpot, Semrush, and Conductor have pages for "what is AEO" and "best AEO tools." They don't have pages for the specific, narrow sub-queries that LLMs generate as supporting searches: "how does ChatGPT decide what to cite," "why is my startup invisible to AI search," "how many AI engines should I optimize for."

Research from multiple studies confirms that pages ranking for both the main query and its fan-out sub-queries are 161% more likely to be cited. The implication is that owning a narrow sub-query isn't just a consolation prize. It's a way to enter the retrieval set for the broader query too, because the LLM merges results across all its sub-queries.

Identifying sub-queries worth owning

The practical question is: which sub-queries should you target? Three criteria matter:

Specificity. The narrower the query, the less competition from high-authority domains. "How to get cited by AI search engines" has major players competing. "How long does it take a new website to get cited by AI search engines" probably doesn't. Both queries might be generated as sub-queries from the same user question.

Relevance to your product. The sub-query should naturally lead to your product or expertise. If someone searches for the narrow question you've answered, your product should be a logical next step.

Absence of quality content. Search the query yourself. If the top results are thin listicles, generic blog posts, or pages that don't actually answer the question, there's an opening. AI retrieval systems are desperate for high-quality, specific content on underserved queries, and they'll pull from smaller domains to get it if the passage quality is high enough.

The Princeton GEO study (published at KDD 2024, analyzing 10,000 queries) found that lower-ranked sites benefit disproportionately from optimization: fifth-ranked websites saw a 115.1% increase in visibility from citation-focused content optimization, compared to diminishing returns for sites already ranking at the top. The long tail rewards effort more than the head does.

Structuring content for sub-query capture

Once you've identified target sub-queries, the content structure matters. Each sub-query you're targeting should have a dedicated section with:

  • A heading that maps closely to the sub-query's phrasing
  • A 50-to-150-word passage directly below that heading which answers the query completely and independently
  • Specific facts, numbers, or named entities that make the passage worth citing over vaguer alternatives

SE Ranking found that pages with 120 to 180 words between headings receive 70% more ChatGPT citations than pages with denser or sparser section structures. The section-level granularity matters because AI search engines extract passages, not pages. Your page doesn't need to rank for the broad topic. A single well-structured section needs to be the best available passage for one specific sub-query.

Strategy 3: Entity creation

The most durable strategy for retrieval set entry is the one that requires the most ambition: create a searchable entity that doesn't yet exist, and become its canonical source by definition.

An entity, in this context, is a term, framework, methodology, or named concept that becomes a searchable noun. When someone coins a term that enters common usage, they become impossible to route around in the retrieval set. No amount of domain authority helps a competitor rank for a term you invented.

This isn't theoretical. "Inbound marketing" was coined by HubSpot. When any LLM answers a query about inbound marketing, HubSpot appears in the retrieval set, not because of domain authority (though they have that too), but because they're the original source of the concept itself. The term is inseparable from the brand.

The mechanism works because of the original source advantage documented across multiple studies. Kevin Indig's analysis of 1.2 million ChatGPT responses found that citation winners are nearly twice as likely (36.2% vs. 20.2%) to contain definitive language like "is defined as" or "refers to." Pages with original data, frameworks, or proprietary concepts consistently outperform pages that aggregate or summarize existing ideas. When you create the entity, you are by definition the original source.

What makes an entity stick

Not every coined term catches on. The ones that work share three characteristics:

They name something people already do but don't have a word for. "Growth hacking" worked because there was already a class of activity (scrappy, metric-driven user acquisition at startups) that lacked a label. The term gave people a way to talk about what they were already doing.

They're searchable. A good entity is 2 to 3 words that someone might type into a search bar. "Answer engine optimization" works. "Holistic multi-paradigm digital presence enhancement" doesn't.

They have definitional content behind them. Creating the term is step one. Step two is publishing the canonical definition page: "What Is [Entity]?" with a clear, specific, independently citable definition in the first paragraph. This page becomes the anchor that LLMs retrieve whenever anyone asks about the concept.

The beauty of entity creation for startups is that it sidesteps the authority problem entirely. You don't need Forbes-level domain authority to rank for a term you created, because no one else has content about it yet. You're not competing for the retrieval set. You're creating a new retrieval set where you're the only occupant.

The structural requirements that apply to every strategy

Getting into the retrieval set is necessary but not sufficient. Your content also needs to survive the reranking stage, where the system evaluates whether a retrieved passage is actually worth citing. These structural factors determine whether content that enters the candidate pool makes it to the final retrieval set.

Extractable passages

AI engines cite passages, not pages. Research from Wellows found that sources with clear, self-contained chunks of 50 to 150 words receive 2.3x more citations than long-form unstructured content. Each passage needs to make sense on its own, without relying on context from surrounding paragraphs.

The practical test: take any section of your article, strip it from its surroundings, and drop it into an AI-generated answer. Does it still make sense? Does it contain a specific, attributable claim? If it starts with "As mentioned above" or uses pronouns with unclear antecedents, it fails the extraction test.

Answer placement

Citation probability is heavily front-loaded. An analysis of 17 million AI citations found that 44.2% of all LLM citations come from the first 30% of text on a page, 31.1% from the middle section, and 24.7% from the final third. The answer to the query your page targets should appear in the first paragraph after the relevant heading, not after an introduction or preamble.

Freshness signals

Content recency is a stronger signal in AI search than most people realize. SE Ranking found that content updated within the past 2 months earns an average of 5.0 citations versus 3.9 for content over 2 years old. Perplexity is especially aggressive on recency: 50% of Perplexity citations reference content published in 2025 alone. Adding explicit temporal markers ("As of February 2026") near key claims and maintaining regular updates keeps content competitive in the retrieval pipeline.

Heading structure

AirOps' 2026 State of AI Search report found that 68.7% of pages cited by ChatGPT follow logical heading hierarchies. Headings that read as natural questions map directly to the sub-queries LLMs generate, making it easier for the retrieval system to match your content to user intent. Pages with FAQ sections average 4.9 citations versus 4.4 for pages without them.

Which engine to target first

Not all AI search engines are equally accessible to startups. The authority thresholds vary dramatically by engine, and a smart entry strategy targets the easiest engines first and works up.

Perplexity has the lowest authority threshold of any major engine and readily cites smaller, niche sites if passage relevance is high enough. Its index spans 200 billion URLs and it processes 200 million queries daily. Perplexity is the fastest way to prove your content can earn citations, and citations on Perplexity generate third-party visibility that helps with harder engines.

Grok cites roughly 24 sources per answer, the highest of any engine, with balanced platform coverage. More citation slots means more opportunities for smaller domains to earn a spot. Grok is the second-most accessible engine for startups.

Gemini weights recency more aggressively than any other engine, which gives new content a structural advantage. A well-optimized article published this week can outperform a competitor's article from 6 months ago on Gemini, even if the competitor has higher domain authority. Gemini pulls 52% of its citations from brand-owned websites, the highest rate among engines.

Claude ignores Reddit, YouTube, Medium, and other aggregator platforms almost entirely, citing only individual company websites and blogs. This makes Claude the one engine where your own domain content has the strongest advantage, provided it meets a high bar for depth and expertise. Claude is accessible if your content quality is genuinely strong.

ChatGPT has the highest authority threshold and behaves most like traditional search, inheriting Bing's domain authority signals. It disproportionately cites Wikipedia, Reddit, Forbes, and other high-authority domains. ChatGPT is the hardest engine for startups to crack and should be the last priority, not the first. The parasitic SEO strategy (getting mentioned on high-authority third-party platforms) is specifically designed to address ChatGPT's authority barrier.

The compounding effect

Every strategy described here compounds over time, which is why the cost of waiting is real.

When your content earns a citation on Perplexity, users see your brand. Some of those users mention you in their own writing, on forums, in comparison articles. Those third-party mentions feed back into the authority signal that retrieval systems use for future citation decisions. SE Ranking found that brands with 10x more web mentions have 10x more AI visibility. The relationship isn't linear at the bottom, but it compounds at scale.

The flip side is equally true. Every month a startup waits, competitors accumulate their own citation momentum. The retrieval set is finite. As competitors fill those 5-to-10 slots per sub-query, the barrier to entry rises. The longer you wait, the more of those slots are occupied by brands that got there first.

AI-referred visitors already convert at 4.4x the rate of standard organic visitors, according to Semrush's 2025 data. And AI referral traffic grew 693% during the 2025 holiday season alone. The channel is growing fast enough that early positioning creates disproportionate returns.

The FogTrail AEO platform ($499/month) automates the full pipeline: querying all five engines simultaneously, identifying which sub-queries you're missing from, generating content engineered for retrieval set entry, and monitoring citation performance every 48 hours. But the strategies described here, parasitic SEO, sub-query ownership, entity creation, are the underlying mechanics regardless of how you execute them.

Frequently Asked Questions

What is the LLM retrieval set and why does it matter?

The LLM retrieval set is the small collection of documents (typically 5 to 10 per sub-query) that an AI search engine considers when generating an answer. The model can only cite sources within this set. Content outside it is invisible during answer generation, regardless of quality. There is no equivalent of page 2 in AI search, which makes getting into the retrieval set the single most important objective for any AEO strategy.

Can a startup with a new domain get cited by AI search engines?

Yes. Research shows that 28.3% of ChatGPT's most-cited pages have zero organic visibility in traditional Google search, and nearly 90% of ChatGPT citations come from URLs ranked position 21 or lower. Startups can enter the retrieval set by getting mentioned on high-authority third-party platforms (G2, Reddit, comparison articles), owning narrow sub-queries that larger competitors haven't covered, and publishing original data or frameworks that make them the canonical source on a specific topic.

Which AI search engine is easiest for startups to get cited on?

Perplexity has the lowest authority threshold and will readily cite smaller, niche sites if passage relevance is high enough. Grok is the second-most accessible, citing roughly 24 sources per answer (the most of any engine), which creates more citation slots for smaller domains. ChatGPT is the hardest due to its strong domain authority bias inherited from Bing's search index.

How long does it take to get into the retrieval set?

Timeline varies by strategy and engine. Third-party platform mentions (G2 listings, Reddit participation) can start influencing retrieval within weeks as AI engines re-crawl those platforms. New content targeting uncontested sub-queries can enter the retrieval set within days on engines like Perplexity that weight recency heavily. Building enough cross-platform presence to consistently appear on harder engines like ChatGPT typically takes 2 to 4 months of sustained effort.

What is parasitic SEO in the context of AI search?

Parasitic SEO means getting your brand mentioned on high-authority domains that AI search engines already trust and cite frequently, such as Reddit, G2, Wikipedia, YouTube, LinkedIn, and Medium. The top 10 most-cited domains across AI search engines are almost entirely third-party platforms, not individual company websites. By establishing a genuine presence on these platforms, startups can enter the retrieval set through domains that already have the authority signals their own sites lack.

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