Chapter 7: Signing Adobe Acrobat Documents
The CoSign client enables you to digitally sign Adobe Acrobat documents using both Adobe Acrobat and
Adobe Reader, as well as add your graphical signature to the PDF file. This enables you to:
Easily sign an Acrobat document – The Acrobat document may contain multiple signatures, and
each signature can be located in a different part of the document. It is also possible to generate
several signatures for the same end-user. If a document is modified, the end-user is notified that the
document was modified and is able to view the specific version of the document that was signed.
Certify an Acrobat document – Certification is more stringent than the regular signature operation.
When a document is certified, it can be defined that no modification can be applied to the document
(not even the addition of a new version to the document), or it can be defined that only certain fields
in the document can be updated.
Certification is available in Acrobat X/XI.
Validate the signature of an Acrobat document – Validation assures you that the document version
that was signed was not modified after it was signed and that a trusted CA approves the user who
performed the signature operation.
The solution for Adobe X/XI also does not require a client installation on the validator’s side.
As part of the CoSign Web Services solution, the CoSign appliance provides a new Web Service mechanism
called Adobe Roaming ID. This mechanism enables Adobe Acrobat X/XI or Adobe Reader X/XI to directly
interface the CoSign appliance for digital signature operations, without requiring the installation of a CoSign
client in the end user’s PC.
Note: Adobe Acrobat includes sophisticated mechanisms for handling digital signatures. These mechanisms
enable you to maintain different versions of the Acrobat document, so that each digital signature actually signs
a different version of the document. Be aware that even if the document is modified, older digital signatures will
be validated against an older version of the document.
Note: CoSign is currently compatible with versions X.x/XI.x of Adobe Acrobat, and versions X.x/XI.x of Adobe
Reader. Refer to the Adobe documentation for complete information on Adobe’s digital signature capabilities.
This chapter describes signing and validating an Acrobat Document using Adobe Acrobat X/XI, as well as
signing and validating signatures using Adobe Reader X/XI.
Signing an Acrobat Document using Adobe Acrobat X/XI
Note: CoSign supports Adobe X and Adobe XI, but the dialog boxes shown in this chapter are Adobe X dialog
boxes. They may differ slightly from the other versions’ corresponding dialog boxes.