A dated, immutable publication of the corpus that a citation can point at.
An edition is a published state of the corpus, labelled and dated. Editions are immutable: a correction produces a NEW edition and an errata entry rather than silently rewriting one somebody may already have cited.
This exists because dates change and documents citing them do not. If a report was prepared against a date we later corrected, the useful question is what we said when the report was written — and a dataset that overwrites itself cannot answer it.
Dossiers carry an edition on the cover. API responses do not currently carry one; what is citable there is the version and corpus build reported by the health endpoint, and saying so plainly is better than implying a guarantee that is not implemented.
An edition is when we published. Assurance is how well we knew it. A well-evidenced date and a badly-evidenced one sit in the same edition.
See also assurance · precision
We hold this as edition label on every dossier; version and db_mtime from /v1/health. See what we hold.