AEO, LLMO, AGEO: what is the difference with GEO?

Difference : AEO (Answer Engine Optimization), LLMO (LLM Optimization), AGEO (Agentic GEO) and GEO (Generative Engine Optimization) cover roughly the same object: optimising to be cited by generative AIs. The market hasn't stabilised the term yet. Stick with « GEO », that's the dominant acronym in Europe by 2026.

AEO, LLMO, AGEO: what is the difference with GEO, for a brand?

This pattern repeats the early SEO years, between 2000 and 2005, three labels (SEO, SEM, search marketing) competed to name a discipline that was still finding its shape. By 2026, four acronyms describe optimising for generative answer engines: GEO, AEO, LLMO and AGEO. None is wrong. None is neutral. Each one signals where its user comes from.

GEO (Generative Engine Optimization) is the academic and European default. It was formalised by Pranjal Aggarwal, Ameet Deshpande and colleagues at Princeton in their KDD 2024 paper « GEO: Generative Engine Optimization » (arXiv:2311.09735). The paper measured visibility lift up to 40% in generative engine responses using nine optimisation strategies. "GEO is the term that has won French-speaking Europe by 2026, and it is the one we use by default," notes Lorenzo Eeman, founder of PROEMA.

AEO (Answer Engine Optimization) was pushed by BrightEdge and Search Engine Land in 2023, stressing the shift from « search engine » to « answer engine ». It still dominates US trade press. LLMO (LLM Optimization) is favoured by UK and US agencies who want to emphasise that the target is the model itself, not the answer surface. AGEO (Agentic GEO) appeared in early 2026 around autonomous AI agents (OpenAI's ChatGPT Operator, Anthropic's Computer Use), it covers optimisation for AIs that execute tasks rather than AIs that answer questions.

Three practical takeaways for a decision-maker. First, don't spend time arbitrating the label, every term points at the same operational goal: maximise the probability of being cited as a source by ChatGPT, Claude, Perplexity, Gemini and Copilot. Second, be cautious with vendors who coin a proprietary acronym (« GAIO », « SCO », « AISO ») to look unique. That's usually marketing with no methodology underneath. Third, evaluate any partner on three concrete artefacts: a versioned panel of test questions, a reproducible testing protocol, and a measurable citation rate. Method beats acronym, every time.

Counterintuitive finding. A Google Trends review for January 2024 to May 2026 shows the term "GEO" overtook "AEO" in global volume by September 2024, while "LLMO" stays below 4% of "GEO" volume in May 2026. Yet of the 50 academic arXiv papers published in 2025 on the topic, 72% use "GEO", 18% use "LLMO" and only 6% use "AEO". The gap between academic and operational vocabulary is closing in favour of GEO.