Signing a PDF document using a predefined signature field

You can also digitally sign a PDF document by using a signature form field that’s already been added to it. To sign a document in a predefined signature form field, you follow these steps:

1. Open your Digital ID file by choosing Advanced➪Manage Digital IDs➪My Digital ID Files➪Select My Digital ID File. The Select My Digital ID File dialog box opens.
2. Select the filename of your user Digital ID in the Digital ID File dropdown list, enter your password in User Password text box, and click the OK button.
3. If the Signatures palette isn’t open and selected in the Navigation pane, choose View➪Navigation Tabs➪Signatures.
4. Click the name of the signature field you want to sign in the Signatures palette to highlight it, and then select Sign Signature Field on the Signatures palette Options pop-up menu to open the Apply Signature to Document dialog box.
5. Enter your user Digital ID password in the Confirm Password text box if necessary, and then modify the settings in the other options (Reason for Signing, Location, Your Contact Information, and Signature Appearance) as desired. Refer to Steps 5 through 10 in preceding post, “Adding a visible or invisible signature to a PDF document,” for details.
6. Click the Sign and Save button to save your changes and signature in the selected signature field in its current location with the same filename.

Alternatively, click the Sign and Save As button to open the Save As dialog box, where you can modify the file’s location and/or save it under a new filename.
As with the other methods of digitally signing a PDF document, after Acrobat finishes saving the signed document, the program displays an alert dialog box, informing that you have successfully signed it. As soon as you click the OK button to close the alert dialog box, you can see your signature in the signature form field. Figure shows you a PDF document after I signed a signature form field beneath the book title and byline.

Adding a visible or invisible signature to a PDF document

When signing a document, you can sign it invisibly so that no signature form field appears in the PDF document, or you can sign it so that all your signature information appears (as designated in the Configure Signature Appearance dialog box), including any graphic that you’ve selected.
To sign a document, take these steps:

1. Open your Digital ID file by choosing Advanced➪Manage Digital IDs➪My Digital ID Files➪Select My Digital ID File.The Select My Digital ID File dialog box opens.
2. Select the filename of your user Digital ID in the Digital ID File dropdown list, enter your password in User Password text box, and click the OK button.
3. Choose Document➪Digital Signatures➪Sign this Document or, if the Sign Task button is open on the Tasks toolbar, click it and choose Sign This Document on the pop-up menu. If the Alert - Document Is Not Certified dialog box appears, you are given the opportunity to add a Certifying Signature to the document, which will be invalidated if unauthorized changes are made. To specify this added security feature, click the Certify Document button and follow the prompts; otherwise, click the Continue Signing button to open the Sign Document dialog box.
4. Select the Create a New Invisible Signature radio button, and then click Next to open the Apply Signature to Document dialog box. Alternatively, if you wish to sign the PDF document with a visible signature, select the Create a New Signature Field to Sign radio button, click Next, and then draw a signature field in the PDF document by dragging the mouse in the area you want to sign.
5. If you want to add the reason for signing the document, your location, or contact information to the signature information (that can be viewed in the Signatures palette), click the Show Options button to expand the Apply Signature to Document dialog box.
6. To include the reason for signing the document as part of the signature information, select the reason from the Reason for Signing Document drop-down list (such as I Am Approving This Document or I Am the Author of This Document). Note that you can edit the reason you select by clicking the insertion point in the text and then inserting or deleting text as needed.
7. If you wish to save your location as part of the digital signature information, click in the Location text box and enter your current location (as in Chicago or Corporate Headquarters).
8. If you wish to include contact information, such as your telephone number, so that coworkers can contact you if they need your certificate in order to verify your digital signature, click in the Your Contact Information text box and enter that information there.
9. If you’re using a visible signature, by default, Acrobat selects Standard Text as the Signature Appearance. To preview how this signature field will appear in the document, click the Preview button. If you wish to select a new appearance for your signature field, select its name in the Signature Appearance drop-down list. To create a new signature appearance, click the New button. To edit the appearance you selected in the drop-down list, click the Edit button, which replaces the Preview button when you select an appearance you created.
   
10. Click the Sign and Save button to save your changes and signature in the document in its current location with the same filename. Alternatively, click the Sign and Save As button to open the Save As dialog box, where you can modify the file’s location and/or save it under a new filename. After you click the Sign and Save button in the Apply Signature to Document dialog box (to save the file with the same name) or the Save button in the Save As dialog box (to save the file in a new location or with a new filename), Acrobat saves the PDF document with your signature and then displays a Certificate Security - Alert dialog box, informing you that you have successfully signed the document.

After you click OK to close this dialog box, you can verify that you’ve signed the document (if you used an invisible signature) by opening the Signatures palette by clicking the Signatures tab on the Navigation pane (if the palette isn’t already displayed in the Navigation pane). To display the detailed information you added to your signature (including the reason, location, and contact information), click the Expand button (the plus sign on Windows and the triangle pointing right on the Mac) to expand the signature information. If you used a visible signature to sign the document, after you click OK to close the alert dialog box, you can see your signature right on the document page. Note that the Signatures palette shown in this figure displays a list of the detailed signature information that also appears (much smaller) in the signature field to the right of the facsimile of my handwritten signature. You can always review the signatory information for a particular signature in its Signature Properties dialog box. You can open this dialog box for a visible signature by right-clicking (Control+clicking on the Mac) the signature field and then clicking Properties on the context menu. You can also open this dialog box (for an invisible or visible signature) by selecting the signatory’s name in the Signatures palette and then selecting Properties at the bottom of the Options pop-up menu.

Signing a PDF document

After you’ve set up your Digital ID, you’re ready to use it to digitally sign off on PDF documents. In digitally signing a PDF document, you add a special signature form field to the document that contains the mark and signing information that you want displayed. The first time a document is signed by you or one of your coworkers, Acrobat saves the PDF file with the signature in a special append-only form. Every time someone digitally signs the document after that, Acrobat saves a new version of the file to which his or her editing changes and signature are appended.
Keep in mind that when you’re viewing a PDF document with multiple signatures, you’re looking at the latest version of the document with all changes since the first time it was signed. If you want, you can view the original version of the signed document side by side with the most current version by selecting the signatory in the Signatures palette and then selecting View Signed Version in the Options pop-up menu. You can also compare the changes between the original signed version and the current document (by selecting Compare Signed Version to Current Version on the same Signatures palette Options pop-up menu).
If you ever decide that you should manually save a PDF document that’s been digitally signed, don’t use the File➪Save command to do it. Use instead the File➪Save As command to save a copy of the PDF document under a new filename. If you use File➪Save to save a signed PDF document, you automatically invalidate all the signatures in it.