This panel is called from the Panel bar by the following tool
If you do not see this tool, right-click in an empty area of the Panel bar and select it.
The Signatures panel provides information on all signatures attached to the current document. Click the Options button at the top to choose from a list of Signature commands.
For more information see About Digital Signatures and Verifying Digital Signatures.
Note
Handwritten signatures do not appear in this panel because they have no linked security. They are treated as stamps and appear in the Comments panel.