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Stamp CONFIDENTIAL on a PDF

Marking a document as confidential does something specific: it removes the excuse. A recipient who forwards a page stamped CONFIDENTIAL on every sheet cannot reasonably claim they did not know its status, which is why the marking appears on board papers, draft contracts, tender responses and anything circulated before it is final.

The same applies to DRAFT. A version that escapes without it can be mistaken for the final one, and the cost of that is usually higher than the cost of stamping it.

A marking is only worth applying if it reaches the person holding the document, which rules out anything a reader can switch off. Some PDF tools add stamps as annotations, and annotations can be hidden by a viewer setting, dropped when a file is re-saved elsewhere, or left out of a printout. A confidentiality notice that vanishes somewhere between you and the recipient is worse than none, because you believed it was there. What this applies survives all of that.

Position, size, rotation and opacity are all adjustable, so a diagonal marking can sit across the page at low opacity without making the text underneath hard to read. The preview shows the result before you commit to it.

Be clear about what a watermark is for. It communicates status; it does not restrict anything. Anyone determined can edit any PDF. If the document needs actual access control, encrypt it with Protect PDF, and use the watermark to say what it is.

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Frequently asked questions

Can the CONFIDENTIAL stamp be removed?

It is drawn into the page content, so it cannot be toggled off in a reader or stripped as an annotation. Anyone determined enough can edit any PDF, so treat it as a clear marking rather than as protection.

Will it make the text underneath hard to read?

Not if the opacity is set sensibly. A light diagonal marking is legible as a marking while leaving the document perfectly readable, and the preview shows exactly how it will look.

Can I stamp something other than CONFIDENTIAL?

Yes. Any text works, so DRAFT, INTERNAL ONLY, a case reference or a recipient name are all straightforward. An image watermark can be used instead if you have a company mark.

Should I encrypt the document as well?

If access genuinely needs restricting, yes. A watermark states the status of a document and an encryption password controls who can open it. They do different jobs and are often used together.

Is the document uploaded to stamp it?

No. The stamping runs in your browser, which matters given that documents needing a confidentiality marking are by definition ones you would rather not hand to a third party.