Three companies from different industries made the same architectural decision over the past 30 days: grounding AI in proprietary data. Marriott launched Ask Bonvoy with responses grounded exclusively in Marriott-owned, verified property data. 3M launched Ask 3M with answers built entirely on verified documentation across its 49 technology platforms. The Travelers Companies trained TravelersLLM on millions of internal documents, and the company says it outperforms every commercially available AI model on insurance-specific tasks. The article states that grounding AI in proprietary data can decrease hallucination rates by up to 90%.