How large and how dark should a Bates stamp be to survive copying and rescanning?

What happens to a stamp across generations

Once a production is delivered, the pages get printed for depositions, copied for witness binders, scanned back into another firm's review platform, and sometimes printed and scanned again for trial exhibits. Each step degrades small text. Thin strokes break up, gray fills into speckle, and characters that were distinguishable at the original resolution start to merge. A digit that looks like a 6 on screen can read as an 8 or a 0 after two rounds of copying, and at that point the Bates number is no longer doing its job. Related: What exactly is Bates numbering and why do law firms rely on it for documents?

This matters most for the characters that carry meaning: the prefix letters and the digits. Confusable pairs like 1 and l, 0 and O, 5 and S, and 8 and B are the usual failures. Serif fonts and light weights make these worse. The goal when sizing and styling a stamp is not just legibility on the first print but legibility after the worst realistic chain of reproduction the document will face. Related: How should a firm choose Bates prefix conventions that stay clear across many matters?

Keep reading: What exactly is Bates numbering and why do law firms rely on it for documents?, How do you keep Bates numbering consistent across multiple separate document productions?, When should you apply confidential or privileged watermarks to a batch of documents?. See how PdfStampr helps you bulk pdf stamping and bates numbering.

Font choice and weight

A clean sans-serif font with open shapes and clear distinction between similar characters holds up better than a decorative or condensed face. Regular or medium weight is usually the right choice: bold can fill in on low-quality copies and turn a 0 into a solid blob, while light weights break apart. Fixed-width fonts have an advantage for numbers because every digit occupies the same space, which helps a reader compare numbers across pages and makes it obvious when a digit is missing.

Whatever font you choose, embed it in the PDF. A stamp drawn with a font that is not embedded will be substituted on the recipient's machine, and the substitute may have different widths, weights, or character shapes. Embedding also guarantees that the stamp prints identically from any viewer. Most stamping tools embed by default, but check the PDF's font list on a sample output rather than assuming.

Size, contrast, and background

For letter-size pages, a stamp in the range of roughly 8 to 12 points is the usual working band. Below 8 points, degradation over two copy generations becomes a real risk; above 12, the stamp starts competing with content and can crowd margins on pages with existing footers. Pure black on white is the safest contrast. Gray stamps look elegant on screen and disappear on a bad copy, and colored stamps become unpredictable grays on monochrome printers. If you want a stamp to be visually distinct from the document, use position and font rather than color. Related: How do you choose where a Bates stamp sits so it never covers document content?

Background treatment is a tradeoff. A solid white box behind the stamp guarantees contrast even on busy pages, but it hides whatever is beneath it and can look heavy. A stamp with no background is cleaner but depends on the margin being empty. A practical compromise is to use no background by default and enable a white box only for a flagged subset of pages, such as scanned images with dark borders or full-bleed photographs, where the number would otherwise be lost.

Testing before you commit

The only reliable test is to reproduce the abuse. Stamp a sample of pages, print them on an ordinary office printer, copy the printout on a copier at default settings, then scan the copy at a typical review resolution. Look at the third-generation result on screen and on paper. If every digit is unambiguous, the settings are safe. If any digit is doubtful, increase size before you increase weight, since size helps more consistently across different copiers.

Include the hardest cases in the sample: a page with a light gray scanned background, a page with dense small text near the stamp, and a page that will be reduced when printed, such as a landscape spreadsheet shrunk to fit portrait. Document the final settings in the matter's production spec so supplemental volumes match and so a colleague can reproduce the test rather than re-deriving it. The whole exercise takes well under an hour and prevents the call from opposing counsel asking which page you meant. Related: How can a small legal team batch-stamp thousands of pages without losing a whole day?