Acrobat Pro 9, password gives no protection, alternatives

The rather obscure answer is "no". Adobe makes much of the security of a PDF but not in the sense you hope - a PDF can be secured against unauthorized [u]opening[/u] and can be certified to detect changes, but the concept of protecting the content from [i]authorized[/i] users is entirely different. Don't get me wrong - Adobe is doing the best it can; it's just fundamentally illogical to ask for something to be both visible and hidden from the same person at the same time.

If someone can get to the point a PDF is displayed on their screen (whatever security you apply, including DRM licensing systems) then they can trivially copy out any bitmap graphics they want just by pressing the PRINT SCREEN button, even if the PDF is set to disallow printing. If the PDF is printable, they can always push it to another non-secured PDF via Distiller, and thereby extract any text, bitmap and vector images that appear on the printed version even if they can't break into the permissions security on the original file.

If your PDF applies watermarks when it prints they are always discrete objects in the PDF tree, so anyone with Acrobat can send the print job to Distiller, re-open the printed PDF and remove them again - hence that won't work either. You could burn watermarks into the artwork itself, but of course that only works for draft versions and demos of your document. On-screen watermarks which don't print, in a PDF which is DRM-secured and set not to allow printing, can't be bypassed by screengrabs but equally a PDF like that serves no purpose!


The only things folks can't easily extract are dynamic and interactive elements (scripts, video, 3D) where the document has DRM-enabled security (e.g. via LiveCycle Policy Server), as they're not passed via screengrab or print, and LCPS-DRM isn't crackable by third-party PDF tools.

There are several ways to make copying of [i]text[/i] a bit more difficult, but the same doesn't apply to graphics. In that sense, there's no real difference between sending someone a PDF and posting the graphic on a web page - they clearly [u]have[/u] to see the thing or it's pointless sending it, and if they can see it, they can snaffle it.

Thank you for your extensive answer. It does clarify a lot. What i'm most concerned about is the the editing of vector graphics. Once the pasword to disable editing is removed, one can open the PDF in a drawing program and "lease" the vector graphics, clearly i'd like to prevent that from happing. I'm not too concerned about bitmaps.