Flattening all text and images in a PDF so it can't be edited

[MisterEditorial]

I am using Acrobat DC to make PDFs and need to flatten all images and text (including a watermark) so they can't be edited or items removed. I have tried using Adobe DC encryption and the password feature but this can easily be removed by non-Adobe software.

I have a project that involves 100s of pre-made PDFs that need a watermark to be added and then 100% flattened as part of the document. Therefore, I cannot apply the watermark in Photoshop or InDesign prior to making the PDF.

Any help greatly appreciated!

[Test Screen Name]

This is an impossible quest. Flattening is not a security measure. Acrobat specifically does OCR to

recognise the text and allow editing if you flatten it,  because people demand this feature. 

[MisterEditorial]

Thanks for your quick reply. It seems odd that there isn't an option for security purposes - flattening with a watermark would prevent the ability of a third party to reproduce work without necessary permissions afterall. I appreciate being able to edit PDFs, but would also think that there would be a feature to secure all content within the file. 

[Test Screen Name]

"flattening with a watermark would prevent the ability of a third party to reproduce work without necessary permissions" No really, it wouldn't. Not for a moment. Acrobat would do OCR in this case. Any other app might do whatever is convenient to their user to allow editing. 

"but would also think that there would be a feature to secure all content within the file. " Well, there is document security. However, the PDF specification is public - that's why PDF is everywhere. That means that it's up to the people who sell software to obey the security rules. Many of them just don't care about our wishes and/or rights to protect stuff. So, I suggest you give up.

Digital signatures are designed to detect any CHANGE to a file, and this is the real security; the file can be changed, or faked, or printed/scanned, or whatever; but the signature will show it was tampered with.

[MisterEditorial]

Thank you. Not the answer I was hoping for, but supports all of my research and attempts to find a workaround. Best Dan

[try67]

You should digitally sign the files. While not making it impossible to edit them it's the only way to prove that a file has been edited, as that would invalidated the signature. Anything else can be overcome by someone willing enough.

[MisterEditorial]

Thanks for your response. I may look to add a watermark in Photoshop prior to makign PDFs in future.