Permanent Watermark

[Guest]

I have alot of PDF's to watermark and noticed they are easily removed.. Is there a way to permanently watermark a PDF?

[Eddie_van_Leeuwen · Accepted solution]

Apply an angle to the watermark and print again => pdf seems to work fine - at least I did not manage to remove the watermark yet

[However using older version 9.5.1 ...]

[try67]

Apply a security policy that prevents editing the file and/or digitally sign it.

[Guest]

Can that be easily removed like the password protected pdf?

[try67]

Not so easily, but it's not impossible to do. Basically there's no 100%

secure way of doing it.

If you really want to make it difficult to remove you should convert the

entire page to an image and then it will only be possible with an image

editor.

[Eddie_van_Leeuwen · Accepted solution]

Apply an angle to the watermark and print again => pdf seems to work fine - at least I did not manage to remove the watermark yet

[However using older version 9.5.1 ...]

[Test Screen Name]

Editing is much improved in Acrobat Pro DC. If it's an image it is converted for editing.

[Ronen288583]

If you're still there---to the novice who needs to apply a permanent watermark---what does digitally-signing it do to make the watermark permanent?  Does it restrict editing?

[Tariq Ahmad · Accepted solution]

Hi @Ronen288583, 

Thanks for reaching out. 

It sounds like you might be referring to how a digital signature in Acrobat makes a document “permanent” or unalterable after signing. Here’s how it works:

• When you apply a digital signature in Acrobat, the document is cryptographically sealed using your digital ID (certificate).

• Acrobat creates a hash (a unique digital fingerprint) of the document’s exact state at the time of signing.

• This hash is encrypted with your private key and embedded into the PDF along with your certificate details.

• If any change is made to the file afterward — even a small edit — the hash no longer matches, and Acrobat will clearly show that the document has been modified after signing.

• This ensures integrity (no one can alter the content unnoticed) and authenticity (verifies the signer’s identity).

In short, it’s not how digital signature locks the “watermark” that you can see; it’s a security seal built into the PDF that’s verifiable by anyone opening it. That’s what makes the signed document “permanent” from a security standpoint.

For more information on Digital Signature: https://adobe.ly/4mhx1Ww

Best regards,
Tariq | Adobe Community Team