If you want to protect your PDF files and ensure they can only be opened on a specific hard drive or USB drive, you can use hardware-based DRM. One of the most reliable ways to achieve this is by obtaining
[Solution] VeryPDF Offline DRM Solution: How We Use Customer Hardware Information (Hard disk serial number, network card Mac address, etc.) to Lock and Protect PDF Files
Using Customer Hardware to Encrypt and Lock PDF Files: The VeryPDF Offline DRM Solution At VeryPDF, we understand that safeguarding your intellectual property is a top priority. That’s why we’ve developed a hardware-bound, offline DRM protection system for PDF files—designed