Someone said it and the scan carried it forward, but nothing in the record supports it. Treat it as a claim attributable to whoever made it, never as an established fact. Analyses that grade their own evidence mark these "asserted, not evidenced".
The definition the product enforces, read from the same code the methodology page renders.
The scan carried the claim forward because someone made it, and found nothing behind it. Treat it as attributable to its speaker. A page with many unverified rows on one subject is telling you that the subject is talked about more than it is documented.
The grade every claim on a research page carries: how it is known, not how confident it sounds. Assigned by the same rules on every scan; the rollup numbers are computed from the graded rows.
Every grade here is assigned by the same rules on every scan, and the methodology page renders those rules from the code that enforces them.