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Sign and certify documents

Digital signatures let you identify any unauthorized changes made to a document after it is signed. Documents may be signed several times and by different persons. Certifying a PDF document ensures, in addition to applying a digital signature, that the range of permitted actions is limited.

The tasks below can be performed more conveniently with the Sign/Certify Panel. This is called from the Panel bar by the following tool:

Sign / Certify icon If you do not see this tool, right-click in an empty area of the Panel bar and select it.

Sign an open PDF document

  1. Use the Sign (Sign icon) tool at Security > Sign. Click the arrow for a drop-down list and select Sign Document.

    The pen cursor (Pen cursor) appears as you hover the mouse over the document area.

  2. Click or draw a signature.
    • Click with the pen cursor in the page, then click Continue to create an invisible signature. A confirmation dialog appears, either click Continue to proceed with an invisible signature, or click Start Over and retry for a visible signature.
    • Click (and hold the mouse button) with the pen cursor and draw a rectangle on the page big enough to contain a signature.
  3. In the Sign Document dialog box, select a Digital ID from the list or click Add to browse for an existing Digital ID or create a self-signed digital ID.
  4. Confirm the password if the signature scheme includes password protection.
  5. If you selected an invisible signature, then click Save or Save As for an invisible signature to take effect.
  6. If you selected a visible signature, then click Next, configure the appearance, and click Save or Save As for a visible signature to take effect.

Sign and certify an open PDF document

  1. Click the down arrow next to the Certify tool in the same group, and select Certify Document or Certify Document Invisibly from the drop-down list.
  2. Draw a rectangle to certify the document with a visible signature.

    The Certify Document dialog box appears.

  3. Select a Digital ID from the list or click Add to browse for an existing Digital ID or create a self-signed digital ID.
  4. Confirm the password if the signature scheme includes password protection.
  5. Select the permitted actions in the Allowed Actions list.
  6. If you selected an invisible signature, then click Save or Save As for an invisible signature to take effect.
  7. If you selected a visible signature, then click Next, configure the appearance, and click Save or Save As for a visible signature to take effect.

Use a signature scheme

To use an available signature scheme, select its thumbnail in the Sign/Certify panel panel and do one of the following:

  • Drag it to the place on the page where you want to locate it with original sizing.
  • Double-click with the mouse pointer on the page where you want it located with original sizing.
  • Draw a rectangle with the mouse pointer to contain the signature, resized to fit into the rectangle.
The Sign/Certify panel displays both visible and invisible signature schemes.