Make every copy identifiable.

A static watermark is burned into the file once and for all: it shows the same text to everyone, usually a company name or a “Confidential” label. It signals that the document is sensitive, but it says nothing about the person looking at it.

A dynamic watermark is generated at view time from the context of the session: the visitor's email, the date, and the time. Two people opening the same document see two different watermarks, so every page on screen can be traced back to a specific reader.

Most document leaks are not technical breaches but informal sharing: a screenshot forwarded in a chat, a PDF passed along “for information”, a photo of a screen taken in a meeting. No access control can stop an authorized reader from photographing their own screen.

A watermark changes the calculation. When a page visibly carries the reader's name, forwarding it means signing the leak. The effect is first and foremost deterrent: seeing your own email address on every page is usually enough to discourage unauthorized sharing. If an incident does happen, the marking gives you a concrete starting point for tracing where the document came from.

You enable the watermark on the room or document concerned, then choose what it should display. Seend composes the text from what is available for the current session: visitor email, date, time, room name.

The marking is applied at render time, in the viewer, not in the stored file. You keep a clean original that can be reused for another share with a different watermark. If downloads are allowed, the file handed to the visitor can carry their marking too.

A watermark that is too faint loses its deterrent effect; one that is too heavy makes the document painful to read and looks unprofessional during a fundraise or a due diligence. The goal is for it to stay noticeable without ever obscuring a table or a chart.

In practice, a repeated diagonal pattern at low opacity works well on dense documents, while a single footer marking is enough on highly visual presentations. Test the rendering on the busiest page of your document before sharing.

A watermark acts on what happens after a document is opened. It should therefore be combined with the controls that decide whether it opens at all: named access, email verification, folder-level permissions, scheduled expiration, and the ability to disable downloads.

Paired with reading insights and the audit log, it completes a coherent chain: you know who was invited, who actually opened the room, what was read, and under which marking. That combination, more than any single setting, is what really protects a sensitive matter.