It depends on the level of protection. When securing a PDF, you can set various features to be allowed or prohibited, e.g, opening, printing, editing, commenting, etcetera. Without the use of somewhat unauthorised tools or knowing the password(s), you can't bypass these restrictions. And note: with the plain Adobe Reader you normally can't save any PDF at all...


Oorspronkelijk geplaatst op Quora: How do you convert a "Secure" PDF into a normal PDF?"