Independent timestamp vs traditional evidence of when a file existed

Independent timestamp vs traditional evidence at a glance

What traditional evidence looks like

• A witness with knowledge. In US federal courts, Rule 901(b)(1) lists "testimony of a witness with knowledge" as one way to authenticate an item, and 901(b)(9) lists "evidence describing a process or system and showing that it produces an accurate result" (FRE 901).
• Certified electronic records. Rule 902(13) and (14) allow certain electronic records and data copied from a device or file to be authenticated by a qualified person’s certification. The committee note explains that data copied from devices "are ordinarily authenticated by ’hash value’" (FRE 902).
• Metadata and logs. File-system dates, email headers and system logs. NIST’s forensic guidance recommends preserving file modification, access and creation times when collecting data, and verifying copies with message digests (NIST SP 800-86). It treats those times as items to preserve and interpret, not as self-proving.
• A forensic examiner’s report. See forensic examination vs an independent timestamp.

What an independent timestamp adds

• A date set by a system outside the parties. The time is recorded on a public ledger, so neither party can adjust it afterwards.
• A check anyone can repeat. Re-fingerprint the file and compare. If it matches, it is the same file. If it doesn’t, it isn’t.
• A record made at the time. A later reconstruction relies on memory and logs. A TimeBind is created while the file exists, so it doesn’t need reconstruction.
• Low cost. Your first Pooled TimeBind is free. After that, from US$5.

A TimeBind is not a qualified electronic time stamp under EU law, and it is not a notarised copy. See RFC 3161 vs blockchain timestamps for how those differ.

How the independent time is recorded

The fingerprint of your file is recorded in a transaction on the Bitcoin blockchain, a public ledger copied across many independent computers. The time comes from the block that holds the transaction, so no single party, including TimeBinder, can alter it afterwards. This is the same approach the open-source OpenTimestamps project uses. You don’t need to hold or use cryptocurrency to make or check a TimeBind, and the ledger holds only the fingerprint, never the file.

Why this matters when AI can edit anything

Generative AI makes plausible documents, images and audio cheap to produce, and metadata can be edited. A timestamp can’t turn that around, but it does something narrower and useful:

• No one can create a valid record for a time that has already passed. If a file has a recorded time, the file existed by then.
• Any edit changes the fingerprint, so an altered version won’t match the original record.

What it does not do is tell you whether the content is genuine, human-made or truthful. An AI-generated image made today can be timestamped today. The timestamp shows when that exact file existed, not where it came from. Pair it with the usual questions about provenance and a witness who can speak to it.

What the rules say, by jurisdiction

This is a general outline, not legal advice. Check the rules that apply to your matter. For deepfake and altered-file evidence specifically, see our plain reading of the rules in the US, England and Wales, and the EU.

• European Union. Article 41 of the eIDAS Regulation says an electronic time stamp "shall not be denied legal effect and admissibility as evidence in legal proceedings solely on the grounds that it is in an electronic form or that it does not meet the requirements of the qualified electronic time stamp". A qualified electronic time stamp enjoys a presumption of the accuracy of the date and time and the integrity of the data (Regulation 910/2014, Arts 41–42). Other time stamps don’t get that presumption.
• United States (federal). Authentication under Rule 901 asks for evidence sufficient to support a finding that the item is what the proponent claims it is. Rule 902(13) and (14) allow certifications by a qualified person for certain electronic records and copied data, with notice to the other side (FRE 901, FRE 902). The 2017 committee notes say a certification establishes authenticity only. The other side may still object on other grounds, such as hearsay or relevance.
• England and Wales. Under CPR 32.19, a party is deemed to admit the authenticity of a document disclosed under Part 31 unless it serves notice that the document must be proved at trial (CPR 32.19). Section 8 of the Civil Evidence Act 1995 deals with proving statements in documents (CEA 1995 s 8).
• Australia. Section 146 of the Evidence Act 1995 (Cth) deals with evidence produced by processes, machines and other devices, and allows a presumption that a process produced the outcome where it is reasonably open to find that the process ordinarily does so when properly used, unless evidence sufficient to raise doubt is adduced (s 146). State and territory rules may differ.

None of these says a timestamp will be admitted or given any particular weight. See also is a blockchain timestamp admissible in court?.

A practical routine for a lawyer or client

1. Preserve the original file and leave it unchanged. Work on a copy. Log who held it.
2. Make a TimeBind of the exact file, or a set of up to 10 files. Use ASAP if you want its own transaction and independent checking.
3. Keep the original, the certificate and a short note of what you did and when.
4. If the matter proceeds, plan how you will authenticate: who can speak to creating the TimeBind, who can explain the check, and whether an expert is needed. See what to give a lawyer.

When an independent timestamp isn’t the right tool

• You need a presumption of accuracy under EU law. Use a qualified electronic time stamp.
• You need a witnessed or sworn document. See timestamp vs notary.
• The question is who wrote it. A timestamp doesn’t answer that.

General information, not legal advice. A TimeBind shows that this exact file existed no later than the recorded time and still matches its fingerprint. It does not show authorship, ownership, copyright status or how any court, tribunal, client or insurer will treat it.