What metadata fields must be preserved through collection and processing so a production is defensible?

Metadata is the data about a document: who created it, when, how it moved, and how it relates to other items. In e-discovery, preserving the right metadata through every step of collection and processing is what lets a producing party show that what it handed over is authentic, complete, and unaltered. Lose or overwrite it, and an otherwise good production can be challenged as incomplete or spoliated.

Fields That Support Defensibility

No single list fits every case, but defensible productions generally preserve:

• Identity and authorship — custodian, author or sender, recipients (To, Cc, Bcc), and the source location or system from which the item was collected.
• Dates and times — created, last modified, last accessed, and sent/received dates, ideally with the time zone normalized and documented.
• File characteristics — original file name, file type or extension, file path, and size.
• Integrity values — a hash value (such as MD5 or SHA-1) calculated at collection to demonstrate the item has not changed.
• Email and message threading — subject, conversation or thread identifiers, and parent/attachment relationships so families stay intact.
• Embedded and system metadata — tracked changes, comments, and properties that travel inside the native file.

Why It Matters

Authenticity and completeness rest on this layer. Hash values and unbroken chain-of-custody records let a party show the evidence is the same item that was collected. Family relationships and threading prevent attachments from being separated from their parents. Accurate dates and custodian fields make the production searchable, reviewable, and verifiable by the requesting side.

Practical Guidance

• Decide the production form early. The Federal Rules of Civil Procedure address the form of producing electronically stored information, and parties often negotiate fields and format in a protocol up front.
• Collect in a way that does not alter source metadata, and log each handling step.
• Document your methodology so choices are explainable and repeatable.

Requirements vary by jurisdiction. State courts, regulators, and non-U.S. systems impose their own rules, so confirm the standards that govern your matter and consult counsel before finalizing a production specification.