Operation Manual

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Electronic signatures
Last updated 4/7/2015
5 For details about the signer’s certificate, such as trust settings or legal restrictions of the signature, click Show Signer’s
Certificate in the Signature Properties dialog box.
If the document was modified after it was signed, check the signed version of the document and compare it to the
current version.
View previous versions of a digitally signed document
Each time a document is signed using a certificate, a signed version of the PDF at that time is saved with the PDF. Each
version is saved as append-only and the original cannot be modified. All certificate-based signatures and their
corresponding versions can be accessed from the Signatures panel.
1 In the Signatures panel, select and expand the signature, and choose View Signed Version from the option menu
.
The previous version opens in a new PDF, with the version information and the name of the signer in the title bar.
2 To return to the original document, choose the document name from the Window menu.
Compare versions of a signed document
After a document is signed, you can display a list of the changes made to the document after the last version.
1 In the Signatures panel, select the signature.
2 Choose Compare Signed Version To Current Version from the option menu .
3 When you’re done, close the temporary document.
Trust a signer’s certificate
Trusting a certificate involves adding it to the user’s trusted identity list in the Trusted Identity Manager and manually
setting its trust level. End users often exchange certificates as needed when using certificate security. Alternatively, they
add certificates directly from signatures in signed documents and then set trust levels. However, enterprises often
require employees to validate the signatures of others without performing any manual task. Acrobat trusts all
certificates for signing and certifying that chain up to a trust anchor. Therefore, administrators should preconfigure
client installations or let their end users add a trust anchor or anchors. For more information on trusting certificates,
see
Certificate-based signatures.
PDF Portfolios and certificate-based signatures
You can sign component PDFs within a PDF Portfolio, or sign the PDF Portfolio as a whole. Signing a component PDF
locks the PDF for editing and secures its content. After signing all the component PDFs, you can sign the entire PDF
Portfolio to finalize it. Alternatively, you can sign the PDF Portfolio as a whole to lock the content of all component
PDFs simultaneously.
• To sign a component PDF, see Sign PDF documents. The signed PDF is automatically saved to the PDF Portfolio.
• To sign a PDF Portfolio as a whole, sign the cover sheet (View > Portfolio > Cover Sheet). Once you sign the PDF
Portfolio as a whole, you cannot add signatures to the component documents. However, you can add more
signatures to the cover sheet.