I'd like to share a really cool tactic I only recently learned.
It prevents unscrupulous people from stealing the content from your .pdf files by copying and pasting.
This method only works with OpenOffice Writer (my preferred Word Processor) although I'm sure it's possible with others that allow for .pdf conversion, and indeed .pdf creation/editing software itself.
However, if you have OpenOffice Writer and write ebooks and reports, or are at the very least considering it then please check this out ...
1). The first thing you need is an OpenOffice document to be converted to a .pdf file.
2). Click on 'File' and from the dropdown menu select 'Export as PDF' - this open a new window that allows you to set various .pdf options prior to exporting your document as a .pdf.
3). The window defaults to the 'General' tab but what you need to do is click on the 'Security' tab.
4). Click on the 'Set permission password' button and enter a 'Password' and then 'Confirm' and then click 'OK'. After you've done this the bottom half of the security tab can now be edited.
5). Ensure the 'Not permitted' option' is checked and the 'Enable copying of content' is unchecked.
6). Click 'Export' and then save your brand new secure .pdf to a memorable place on your hard drive.
Now when your customers or subscribers open your .pdfs they'll be secured and the option to copy any content from that .pdf removed.
Hope this helps you guys.
EDIT : This will not password protect your .pdfs as that is something completely different.