Bates numbering (also called Bates stamping) is a method of applying unique sequential identifiers to every page of a document set. It's named after the Bates Automatic Numbering Machine, invented in the late 19th century.
Purpose of Bates Numbers
Bates numbers serve several critical functions in legal proceedings:
Unique Identification
Every page in a document production receives a unique number, making it possible to reference any specific page precisely during depositions, hearings, and trial.
Organization
Large document sets (often millions of pages) become navigable through sequential numbering and range references.
Integrity
Bates numbers help verify that document sets are complete — missing numbers indicate missing pages.
Communication
Attorneys can reference specific pages unambiguously: "See Exhibit A, Bates 00045-00048."
Numbering Conventions
Format
Typical Bates number format: PREFIX + Sequential Number
Examples:
- ABC000001 through ABC050000
- SMITH_00001 through SMITH_12345
- DEF-000001-000001 (document-page format)
Rules
- Numbers must be unique within a production
- Prefix identifies the producing party
- Numbers are sequential and continuous
- Each page gets its own number (not each document)
Bates Numbering in E-Discovery
In modern electronic discovery, Bates numbering applies to:
- Native files: Metadata tag with Bates range
- TIFF/PDF images: Stamped on each page image
- Email: Each page of a printed email gets a number
- Attachments: Numbered sequentially after their parent
Technology
Modern litigation support software automates Bates numbering:
- Batch application to thousands of documents
- Endorsement (stamping) on page images
- Load file generation with Bates references
- Cross-reference tracking between productions
Best Practices
- Plan numbering scheme: Agree on format before production begins
- Maintain continuity: Don't skip or reuse numbers
- Document ranges: Track which Bates ranges correspond to which custodians or sources
- Quality check: Verify numbering before production delivery