Case study: Gumlet turned ChatGPT mentions into 20% of inbound revenue. Read it →
The Visibility Vacuum Theory: why GEO closes on a category-by-category timeline.
Capturing the #1 ChatGPT citation in your category costs roughly $400 to $600 today. In 24 months, the same position will cost $5,000 or more, and at that point you will not be capturing it. You will be paying to displace whoever got there first.
The theory in six lines.
Every B2B SaaS founder running GEO investment in 2026 should be able to repeat these six points back after reading. Stage diagnosis is the first move. Everything else follows.
GEO is not evergreen. Each B2B SaaS category opens, fills, and closes its own Visibility Vacuum on a 24 to 36 month timeline.
Capture during Open Vacuum runs $400 to $600 per #1 citation. Displacement during Closed Vacuum runs $5,000 or more, a 50x to 100x increase.
A vacuum is open while four conditions hold: 30%+ YoY demand growth, fewer than 5 dominant cited sources, drifting category vocabulary, and missing comparison pages.
"Best CRM software" was unstable month-over-month in 2024 across DerivateX biweekly tracking. By Q1 2026 the top 5 had been stable for 9 straight months. The category closed in real time.
REsimpli captured #1 ChatGPT for real estate investor CRM in 90 days when that category was open. The same play is no longer available at any price in that category.
Two questions decide your next quarter. Is your category open or closed? And if closed, are you displacing the right position or pivoting to an adjacent vacuum?
Most agencies are selling effort. Not timing.
Every GEO agency you talk to right now is telling you the same thing. The window is closing. Start now. Invest in citation engineering. Get cited before competitors do.
None of them are telling you which window. None of them can answer "is my specific category still open?" because none of them are tracking citation stability across a 12-month observation period. The "start now" advice is the same generic urgency you have heard for two years, and it has produced exactly the outcome you would expect: B2B SaaS marketing teams pouring effort into categories that closed 18 months ago, getting nothing back, and concluding GEO does not work.
GEO does work. You are running it in the wrong category at the wrong time.
The framework below tells you which categories are still open, what it costs to enter them, and what to do if your category has already closed. Run it before your next planning conversation.
What "best CRM software" tells you about category closure.
DerivateX has tracked top-5 cited sources for major B2B SaaS buyer queries biweekly since early 2024. This is what category closure looks like from the outside: source rotation collapsing into a stable set of five names, in roughly the same order, month after month.
Four conditions decide whether your category is still open.
A Visibility Vacuum is open when all four hold simultaneously. Two failing means the vacuum is filling. Three failing means it is closed and only displacement-tier economics apply. Four hours of focused work answers the question.
Demand Growth Rate
The category's primary buyer queries must be growing in search volume. Flat or declining categories rarely produce vacuums because the model's category knowledge has settled.
Test: pull Google Trends and keyword tool data for the last 24 months. Score it.
Authority Gap
If 5 or more sources rotate through the top positions inconsistently, the gap is open. If the same 3 to 5 sources appear across 70%+ of responses, the gap is closing or closed.
Test: run 10 buyer queries 3 to 5 times each across ChatGPT, Perplexity, Claude, and Gemini. Tabulate cited sources.
Definitional Drift
Multiple terms compete for the same concept. The most underrated of the four conditions. LLMs cannot lock in canonical sources for a category whose name keeps changing.
Test: if three or more terms are in active use across review sites and industry publications, drift holds. If the vocabulary has consolidated, drift has closed.
Programmatic Whitespace
If fewer than 3 comprehensive ranking pages exist for "best [category]" queries, whitespace holds. If 5 or more strong pages exist, whitespace has closed.
Test: search G2, Capterra, and the top 5 industry publications for "best [category]" pages. Count them.
Four stages. One non-negotiable cost curve.
Every B2B SaaS category cycles through these four stages. Cost-per-citation rises 50x to 100x from Open to Closed, driven by source preference bias inside large language models. The figures are directional, derived from DerivateX engagement work and live displacement-tier rates.
REsimpli: what Open Vacuum economics look like.
In 2024, real estate investor CRM was a textbook Open Vacuum. All four conditions held simultaneously. Inside that window, REsimpli captured the #1 ChatGPT citation for the category in 90 days using Citation Engineering on definition-forward category pages, comparison content, and named-entity reinforcement.
Where you are right now.
If you are reading this, you are in one of three positions. Run the four-condition assessment on your most important category and the answer is one of the cards below. Starting now is meaningless advice without knowing which one.
Your category is open
All four conditions hold for your primary buyer queries. You are wasting the window every month you do not act. The brands that capture canonical citations in the next 6 to 12 months will be the brands AI models cite for the next 24 to 36 months at minimum.
Your category is filling
Two of the four conditions have failed. You can still capture sub-category positions if you move now and pick your fights carefully. Your window is shorter than you think, probably 6 to 9 months before sub-category positions also lock in.
Your category is closed
Three or four conditions have failed. Your current GEO spend, if it is aimed at the parent category, is theater. The math says you are paying displacement-tier costs to chase positions incumbents will keep.
Common questions from operators.
Run the four-condition assessment this week.
Block four hours. The output is a clear stage answer for your single most important category. Then make the call. Push, pivot, or displace. Do not run a fourth play. There isn't one.
Pick the one category that matters
The single category your business depends on most for revenue. Not three. One. The assessment scales, but the decision quality drops with each parallel category.
Score the four conditions
Demand growth, authority gap, definitional drift, programmatic whitespace. Each one is a yes or no answer backed by 30 to 60 minutes of research. Be honest with the answers.
Decide: push, pivot, or displace
Open means push. Filling means pivot to a sub-category. Closed means either displacement-tier sustained campaign or pivot. Match the move to the stage. Commit budget like the math is real, because it is.
Connected frameworks and data.
Allocate B2B SaaS search effort by retrieval surface instead of channel. The companion budget logic to vacuum-stage timing.
FrameworkThe execution methodology that operates inside an Open Vacuum window. How DerivateX engineers AI citations for B2B SaaS.
Case Study90-day capture of #1 ChatGPT citation for real estate investor CRM. The Open Vacuum economics in detail.
Report50 B2B SaaS brands scored across 1,400 buyer-intent prompts. The data set behind the vacuum-closure observations.
Apoorv is the co-founder of DerivateX, a B2B SaaS Generative Engine Optimization agency that engineers AI citations in ChatGPT, Perplexity, Claude, and Gemini. He authored the 2026 AI Visibility Benchmark Report and the Citation Engineering methodology, and runs the only published biweekly citation stability tracking dataset in B2B SaaS GEO.
Most agencies sell effort. The question is timing. Diagnose the stage. Then commit budget like the math is real, because it is.
