LLM Hallucination

When AI systems generate false, inaccurate, or fabricated information that appears plausible but is not factually correct.

AI
Updated December 20, 2025

Definition

LLM Hallucination refers to instances where large language models generate information that is false, inaccurate, or completely fabricated, yet presented with the same confidence as accurate information. These hallucinations can range from minor factual errors to entirely invented claims, citations, or statistics.

For brands, LLM hallucinations present both risks and opportunities. Risks include AI systems making false claims about your brand, inventing negative information, or providing inaccurate product details. Opportunities exist in positioning your brand as a reliable source that helps prevent hallucinations through accurate, well-structured content.

Hallucinations occur because LLMs predict plausible text rather than retrieving verified facts. They may combine information incorrectly, fill gaps with invented details, or generate citations that don't exist. Systems with real-time search (like Perplexity) can reduce but not eliminate hallucinations.

Mitigating hallucination risks requires maintaining accurate, consistent brand information across the web, monitoring AI outputs for inaccuracies, creating authoritative content that AI can cite correctly, and promptly addressing any false information that spreads.

Key Factors

1
Information accuracy
2
Consistent messaging
3
Source authority
4
Monitoring
5
Correction strategies

Real-World Examples

  • 1

    AI inventing a product feature that doesn't exist for a brand

  • 2

    AI citing a non-existent study or statistic about a company

  • 3

    AI attributing a quote to an executive who never said it

Frequently Asked Questions about LLM Hallucination

Learn more about this concept and how it applies to AI search optimization.

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Also Known As

AI Hallucination
LLM Confabulation
AI Fabrication

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