PDF security

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With Nitro PDF Professional you can secure your PDF files with password- or certificate-based security, and once secured, your PDFs are protected with high-level 128-bit RC4 or 128-bit AES encryption.

Password security for PDF
Certificate security for PDF
Security permissions settings in PDF
Apply security profiles
Digital IDs

• Create a digital ID
• Add people to your Trusted Contacts

You can apply two different sorts of security to control who can access your files and what they can do with the files when they receive them:

• Open file. This security locks a file so that only users with the correct 'key can open the file. Depending on the type of security you use, only users with the correct password, or an approved digital ID will be able to open and view the file.
• File usage permissions. This security can lock (or turn off) particular functionality once a PDF file is opened. For example, you could disallow users from printing or copying text from the PDF. This type of control of document usage works particularly well for certificate-based security as you can allow different usage on a recipient-by-recipient basis.

To view the security in a file:

1. Click the Nitro PDF Button, and then click Document Properties.
2. Click the Security tab.