Atlas searches 5public collections directly and links you to the publisher's own copy of each document. It holds no copies of its own, so nothing here is behind an account, a payment or a login — and every result names the collection it came from and that collection's licence, because two of these are open on condition of attribution.
This is not a search of the public record. It is a search of the collections Atlas has confirmed it can reach — 11 more are listed in the corpus registry and are not searchable yet, and a query returning nothing means these collections held nothing matching it, not that no such document exists.
Results are grouped by collection and never merged into one ranking: Atlas cannot compare a relevance score from a government register with one from a scholarly index, so it does not pretend to. Up to 3 collections per search — one of them answers in two requests, because its search returns identifiers and nothing else.