How do you protect PDF files from copying, unauthorized distribution or sale?
Here are several ideas you can use:
1. Password Protect Them
2. Watermark them
3. Footnotes or headers with copyrights/names/declarations
4. Individual name stamps on the cover (automated using Gumroad).
5. Add a catalog with inviting incentives for freebies, products, and services and links to the back of each pdf file so whioch turns the act of sharing (authorized or unauthorized) into viral marketing
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