Making a PDF that can't be downloaded or read when forwarded

[A_K_Noorian@adobeforums.com]

I want to make a PDF that I can send to a few people on my list. I know how to password protect it. How can I make it so that if the e-mailed file is forwarded to someone besides the intended recipient, the file cannot be downloaded or read? I have looked at the help topic of "Encrypting PDF files for a list of recipients", but this involves building a list of trusted identities, which means getting certificates from everyone I want to put on the list. This seems like a very cumbersome process, as I'm sure some of the people on the list don't know anything about certificates. Is there an easier way to keep a pdf from being forwarded and read? I am using Acrobat 6.0.2.

[Aandi_Inston@adobeforums.com]

You cannot stop a file from being saved, copied, or e-mailed. All you
can do is try to make it that when the file is shared with someone
else, that they can't open it.

DRM (Digital Rights Management) is the traditional approach to this
problem, but digital signatures provide an alternative (really,
another kind of DRM). It certainly requires administration, since you
have to control who can open which file.

Aandi Inston