---
id: "entity-claude-sonnet-4-5"
type: "entity"
entityType: "tool"
canonicalName: "Claude Sonnet"
aliases: ["Claude Sonnet 4.5", "Claude"]
source_timestamps: ["§ Testing AI Brand Desirability", "\\\"§ Explicit Signals Translate", "Implicit Meaning Doesn’t\\\""]
tags: ["llm", "anthropic"]
related: ["claim-model-idiosyncrasy"]
sources: ["geo"]
sourceVaultSlug: "hbr-seg-geo"
originDay: 3
articleStem: "hbr-new-29-luxury-brands-optimize-for-ai"
sourceUrl: "https://hbr.org/2026/06/llms-misunderstand-luxury-brands-heres-how-to-optimize-your-marketing-strategy-for-ai"
sourceTitle: "LLMs Misunderstand Luxury Brands. Here’s How to Optimize Your Marketing Strategy for AI."
---
# Claude Sonnet 4.5

**Type:** Tool (LLM) · **Vendor:** Anthropic · **Canonical name:** Claude Sonnet

One of the three Large Language Models tested in the authors' experiments (alongside [[entity-chatgpt-5-1]] and [[entity-gemini-3-pro]]). Sampled 150 times each across luxury stimuli ([[claim-ai-ignores-implicit-cues]]) and part of the 5,400 car-brand evaluations ([[claim-luxury-hierarchy-flat]]).

**Signature behavior:** Unlike ChatGPT and Gemini, Claude Sonnet 4.5 showed a **heightened willingness to pay** for a Ferrari when it was placed in a luxury context (next to a Van Gogh painting) — the divergent pole in [[claim-model-idiosyncrasy]].

**Enrichment / version caveat:** The supplied sources confirm Claude (Anthropic's model family) was one of the evaluated systems but do not confirm the exact "4.5" version label. Treat the version as reported-by-source.