Adding a watermark that survives someone copying your PDF

A watermark exists to make clear who a document came from, or that it's a draft rather than a final version — but only if it's actually hard to remove. A watermark that's easy to crop out, or that only covers a corner of the page, doesn't do much beyond looking official.

What makes a watermark hard to remove

A watermark drawn once, small, in a corner, can simply be cropped away with any basic PDF or image tool — the rest of the page is untouched, so cropping costs nothing. A watermark that's rotated diagonally, semi-transparent, and repeated or sized to cover most of the visible page is a different problem: removing it means also removing or covering the content underneath, which is a much bigger job than a simple crop.

Text vs. image watermarks

• A text watermark ("CONFIDENTIAL", a company name, "DRAFT") is quick to add and works well for most everyday cases — labeling a document's status or origin.
• An image watermark — a logo — is worth using when brand recognition matters more than a short label, and can be combined with adjustable opacity so it doesn't overwhelm the page underneath.

What a watermark doesn't do

A watermark is a visible deterrent and an attribution mark, not a security measure — it doesn't stop someone from reading, copying the text, or redistributing the file, and a determined person with basic image-editing skills can eventually paint over it. If the goal is actually preventing access rather than labeling the document, that's a job for a password (Protect PDF) instead of a watermark.