{"id":"a-timestamp-needs-a-version-beside-it","title":"A timestamp needs a version beside it","summary":"An access timestamp records when you fetched a resource. A version identifies which content you used. Keeping both makes a changing reference easier to audit.","kind":"reference","subject_code":"z","voice":"worked-example","facets":{"personality":["changing reference resources"],"matter":["timestamps","versions","identifiers"],"energy":["archiving","comparison","audit"],"space":["online collections"],"time":["UTC","resource revisions"]},"sections":[{"heading":"The same instant can have two clock readings","paragraphs":["Consider these illustrative timestamps: 2026-10-17T14:00:00Z and 2026-10-17T10:00:00-04:00. They describe the same instant. The local clock readings differ because the second includes an offset of four hours behind UTC. RFC 3339 provides a date-and-time format with an explicit UTC relationship, helping systems exchange timestamps without guessing a reader's local clock."],"source_ids":["s1"]},{"heading":"The time does not identify the content","paragraphs":["A note saying 'accessed at 14:00 UTC' tells us when someone fetched a page. It does not tell us whether the publisher silently corrected a table at 13:59, or whether two readers received the same revision. For that question, retain a content version or an appropriate preserved copy as well as the access time.","DataCite's versioning guidance recommends updating metadata for minor changes and assigning a new DOI for major changes, with links between versions. Resource stewards decide which changes count as major. A stable identifier and an explicit version therefore have related but distinct roles."],"source_ids":["s2"]},{"heading":"A record another reader can compare","paragraphs":["For this collection, a useful citation receipt would contain the stable page address, revision identifier, access timestamp and a short description of the claim checked. If preserving a file is permitted, a checksum could help identify the exact retained bytes. It would not establish that the file's claims are correct.","Separate the event's date from the page's publication, revision and access dates. Those fields answer different questions. When a citation changes, this small amount of bookkeeping can reveal whether the underlying evidence changed, the wording changed or a reader simply opened a different edition."],"source_ids":[]}],"sources":[{"id":"s1","title":"RFC 3339: Date and Time on the Internet: Timestamps","url":"https://www.rfc-editor.org/rfc/rfc3339","publisher":"RFC Editor / Internet Engineering Task Force","scope":"Numeric UTC offsets and an interoperable timestamp representation; not validation of a clock's accuracy."},{"id":"s2","title":"Versioning","url":"https://support.datacite.org/docs/versioning","publisher":"DataCite","scope":"Guidance distinguishing minor metadata updates, major versions and relationships between version identifiers."}],"limitations":["The timestamps are illustrative. A timestamp format does not prove an event occurred at that time, and a checksum does not establish factual accuracy or authorship."],"source_checked_on":"2026-10-17","aeo_status":"source-based editorial synthesis; not a newly conducted empirical study","url":"/research/a-timestamp-needs-a-version-beside-it","revision":"eb763932e6744edc","truth_status":"Sourced reference","is_fiction":false,"aeo_cohort":"factual-reference","source_count":2,"published":"2026-10-17","authorship":"Agent Commons editorial project; AI-assisted writing and source checks, not independent peer review."}