How do I Bates stamp a batch of PDFs at once?

What a batch does that a per-file tool cannot

Handing the same job to a one-file-at-a-time stamper forty times is not slower by a factor of forty, it is wrong in a different way: you have to carry the next start number in your head across forty runs, and one mistake produces either a gap or a duplicate. A gap invites the accusation that a document is missing; a duplicate means two different pages answer to the same address.

Running the set as a set moves that arithmetic into the tool. If you need a round number at each document boundary, reserving a thousand per document is a checkbox rather than forty pieces of manual counting. If earlier productions already consumed ranges, you declare them once and the run refuses to reissue a number.

Why there is no queue and no size limit to argue with

The encoder for a batch upload service is somebody else’s CPU and somebody else’s bandwidth bill, which is why free tiers there cap files, cap pages, and put you in a queue at the busy hour. Here the work happens in your own tab — pdf-lib reads and writes the bytes on your machine — so a hundred documents cost the operator nothing and there is no queue to be in. The only ceiling is what your browser can hold in memory at once.

It also means the confidential set never leaves the building, which for a production under a protective order is not a nice-to-have.

Stamps and numbers in the same run

Numbering, confidentiality legends and exhibit labels are three independent layers with their own corner, font, size and page range. A set that needs a continuous number on every page and CONFIDENTIAL on every page and an exhibit sticker on each first page is one pass, not three — and the manifest records the exhibit label next to the BegBates and EndBates for each document.

What comes out

The stamped PDFs go to a folder you pick, or to a ZIP when the browser cannot write to a folder directly. With them: a manifest CSV with one row per document — source name, output name, page count, BegBates, EndBates, SHA-256 — and, if you want them, a Summation .dat load file and an Opticon .opt image load file with one row per page.

Any file that will not re-open after stamping is reported and withheld rather than delivered. A page that is missing its expected number is a warning you can chase before the set goes out, which is a much better place to find it than in a letter from the other side.