01 · History
Edwin Bates and the paging machine.
In 1891, Edwin G. Bates filed a US patent for a small mechanical numbering device that automatically advanced its tag wheel each time it was pressed onto a piece of paper. Bates sold it to law offices as a faster and more reliable way to mark sequential numbers on documents than a clerk by hand. Litigators borrowed the device to mark documents being produced, and by the 1920s — well before the term "discovery production" existed — the practice of putting a Bates number on every page of every document under a single legal-discovery cover became standard. The mechanism survived into the photocopier era, then the laser-printer era, and now exists almost entirely as software stamps on PDFs.
02 · Format
How Bates numbers are formatted.
A Bates number is built from up to four parts: a firm or case prefix, a separator, a zero-padded sequence number, and an optional suffix used for confidentiality designations. The prefix and the zero-padded number are mandatory; the rest are matters of convention.
SMITH-000847-CONF
In the example above: SMITH is the case identifier, 000847 is the page number (zero-padded to six digits so the file sorts correctly as a string), and CONF is a confidentiality designation. Most matrimonial firms in 2026 use a six-digit padding — that leaves room for productions up to 999,999 pages, which is more than any real divorce case will ever produce.
03 · When you need it
When Bates stamping is required.
Bates stamping is not technically required by the Federal Rules of Civil Procedure, but it is the universal convention. You will encounter it in:
- Discovery production in response to a Demand for Discovery & Inspection — every page of every responsive document gets a Bates number before it goes to opposing counsel.
- Motion practice — every cited document is referenced by Bates range, not by a vague "see Exhibit A."
- Depositions — the witness is handed a stamped exhibit with a Bates number; the court reporter records the citation.
- Trial — exhibits arrive Bates-stamped, often with a layered trial-exhibit number on top.
If you produce documents to opposing counsel without Bates stamps, expect a meet-and-confer letter within a week.
04 · Methods
How it's actually done in 2026.
Three approaches dominate. Each is a step further from the original 1891 device.
A.
Adobe Acrobat Pro's Bates Numbering
The only universal method. Built into Acrobat Pro. Manual, single-file, no continuity across productions unless you remember the last number. Fine for productions under a few hundred pages.
B.
eDiscovery platforms
Everlaw, Relativity, and others bundle Bates stamping as part of a coding platform. Excellent for corporate litigation; sized and priced for it. A divorce solo or small firm pays for capabilities they will not use.
C.
AI-native discovery tools
Tools like BatesFlow do both classification of the production and stamping in a single pipeline. No combining and re-combining PDFs by hand to make the numbering reflect the document boundaries — the document boundaries are detected first, then the stamping respects them.
If you're producing in family law
Here's how AI does this.
BatesFlow stamps a 10,000-page divorce production in twelve minutes. If the historical context above is interesting and the practical version is more interesting, see the AI Bates stamping for family law use-case guide.