Web archives and dated captures, explained
How web archives capture pages, how courts treat archived captures as evidence, and the rules on changing terms, policies and prices.
Updated 6 November 2026
Data tools
- Web archives
A sourced directory of the Internet Archive and national web archives in the UK, US, France, Canada, Australia, Japan and other IIPC member countries.
- Evidence rulings
Court and board rulings from the US, EU, Australia and the European Patent Office on whether archived web captures can prove what a page showed.
- Standards
Technical standards and legal rules that define how web captures are stored, dated, time-stamped and proved, from RFC 7089 and ISO 28500 to eIDAS.
Web archives
- How web archives work: crawlers, captures and gaps
How the Wayback Machine and national libraries capture web pages, what the date in an archived URL means, what gets missed and who decides.
- National web archives compared: who collects, under what law, and who can see it
How the British Library, Library of Congress, BnF, Library and Archives Canada, NLA and Japan's NDL collect websites and who may view the captures.
- The Memento protocol explained: asking the web for a page as it was on a date
How RFC 7089 Memento works: original resources, mementos, TimeGates, TimeMaps, the Accept-Datetime and Memento-Datetime headers, and its limits.
Captures as evidence
- How to cite an archived page: what to record so others can find the same capture
What to record when citing a Wayback Machine or other archived page: original URL, archive URL, capture time, archive name, and how courts handle link rot.
- Trusted timestamps explained: RFC 3161 tokens and EU qualified time stamps
How an RFC 3161 time-stamp token proves data existed at a time, what a Time Stamping Authority signs, and the legal effect of EU qualified time stamps.
- Wayback Machine captures as evidence: how courts in the US, EU and Australia treat them
What US appeals courts, the EU General Court, the Federal Court of Australia and EPO boards have said about Wayback Machine captures as evidence.
Prices and terms
- Rules on notice of changes to terms of service: EU, UK and how old terms are proved
The EU 15-day notice rule for platform terms, UK rules on unilateral changes to consumer contracts, and how archived captures prove old terms.
- The EU prior price rule explained: Article 6a and the 30-day lowest price
How Article 6a of Directive 98/6/EC works: the 30-day lowest prior price, exceptions, the 2024 Court of Justice ruling and the US former price rule.