I know of one way that should work in Mac as well, it works in 2007 and 2010 for PC. Microsoft does offer a very expensive digital signing way too.
However, I think this will work out for you pretty well. Open a word document, click the developer ribbon (these steps may not be 100% the same as yours as I don't have 2011 for Mac available to be at the moment).
What you're looking for in the developer portion is Restrict Editting
. Then on the right, it'll ask you what editting you'd like to restrict it to. Change it to FORMS
mode, and then apply the changes. It will ask for a password (this is to allow future editting).
After changing it to forms mode and locking it with a password, they'll no longer be able to highlight the words and such to do an easy copy. If they try to bypass it by resaving it using save as it will still carry the same restriction.
Let me know how it goes for you or if you're unable to find the right settings. The developer ribbon can be enabled by clicking the little gear/wheel at the top right I believe, then you'll be able to enable it. For Word 2007/2010 its enabled by default.
Or you can go to Word
and check it from there.
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