# Arieta Data Version History

> Arieta Data Version History is every content-hash version of every document the pipeline has observed, with fetch timestamps, so models and evals can be built point-in-time without leakage from later amendments.

URL: https://data.arietalabs.com/datasets/history/
Croissant: https://data.arietalabs.com/datasets/history/croissant.json
Datasheet: https://data.arietalabs.com/datasets/history/datasheet/
Free sample: https://data.arietalabs.com/samples/history.jsonl.gz

- Records: 15,098 versions as of the November 2026 snapshot
- Unit: one record per document, language and version
- Formats: Apache Parquet (zstd-compressed, sharded at about 512 MB, one directory per SKU and lane); JSON Lines (gzip) (jsonl.gz, same records and field names as Parquet)
- Updates: monthly delta snapshots with upserts and tombstones
- Use cases: Point-in-time evals without future leakage; Temporal and amendment-aware training; Diff supervision: what changed between versions

## Schema

| Field | Type | Nullable | Description |
| --- | --- | --- | --- |
| celex | string | no | CELEX number (EU) or national id. |
| language | string | no | ISO 639-1 language code. |
| jurisdiction | string | no | Lane code. |
| version | int64 | no | Version number, 1 = first observation. |
| contentHash | string | no | SHA-256 of the normalised parsed text of this version. |
| fetchedAt | timestamp | no | When this version was observed upstream. Version N is current from its fetchedAt until version N+1’s. |
| title | string | no | Title at this version. |
| articleCount | int64 | no | Number of articles in this version. |
| diffSummary | string | yes | Short human-readable summary of what changed from the previous version. |
| articles | list<struct> | no | Full article text of this version (same structure as the corpus). |
| articles.id | string | no | Article id within the document (e.g. art_5). |
| articles.number | string | no | Article number as printed. |
| articles.title | string | yes | Article heading. |
| articles.text | string | no | Article text, normalised whitespace, no HTML. |
| articles.repealed | boolean | no | True when the source marks the article as repealed (schema 1.2.0). Filter on it to keep in-force articles only. |
| snapshotId | string | no | Snapshot the record belongs to. |