Brand mentions in LLMs refers to the frequency and sentiment with which large language models such as GPT-4, Claude, and Gemini spontaneously reference a company, product, or service name when responding to relevant prompts, even without being asked to cite a source. Because LLMs are trained on large corpora of web text, brands that appear frequently and positively in high-authority sources, industry publications, review platforms, and forums are more likely to be encoded into model weights and surfaced in generated responses. SEO and digital PR practitioners increasingly track brand mentions in LLMs as a proxy for brand authority in AI-mediated environments, treating it as an analogue to share-of-voice metrics in traditional media. Strategies to improve LLM brand presence include earning coverage in publications known to be included in training data, maintaining consistent entity information across the web, and generating genuinely quotable content that becomes part of the broader conversation about a topic.