As George states, the digital signature covers the whole document, and only the whole document. It has threefold purpose: sealing the integrity of the document, adding a time stamp, and identifying the signer. In paper-based workflows, many organizations require that the user signs every page of a document. This signature's purpose is -- besides providing business to the pen makers -- probably a confirmation that the signer has read the according page. This does not coincide with any of the purposes of the digital signature. In my humble understanding, the PDF/Acrobat equivalent of such a signature would be a stamp using an image of the wet signature of the signer.

Hope this can help. You need to specify exactly what you want to do. You can apply a 'signature' comment/annotation stamp to each page, but this is not secure and does not indicate if the document has been modified after the signature was applied. You can apply a digital signature to entire document that will indicate that the PDF was changed after the document was signed and is also considered to be equivalent to a pen and ink signature in many countries for legal documents. Maybe a combination of both methods would be appropriate. One also should consider what data should be included in the stamp image.

Here is an easy trick to scan your signature into your Mac which you can add to any PDF document using only software that comes pre-installed on the Mac. Checkbox for word document. Create a Transparent Signature Stamp.

This is more of a suggestion, because it seems some industry sectors, such as mine, need a signature to appear on each page. Contractors still use paper plans to take at projects and the digital signature, with whatever features we want it to have, should appear on every page, because of trust and regulation issues. Although I'll push for the use of the Stamp feature, it will still look odd and, for us, unofficial. The signature feature should provide for the signature 'image' to appear, at least, on the same position in each page. I think this shouldn't be difficult from a software standpoint, certainly not for the programmers of Adobe.

This way, for organizations that need it, they can regulate for a clean space on the same position to be provided in each of the design pages.

The Preview application in OS X has an excellent option for and inserting them into PDF documents. This is great for signing forms, letters, and other items that require a signature. The process for doing so simply involves capturing a written signature with a Web cam, after which you can append them to any PDF document open in Preview. Signatures that you associate with Preview in this manner are stored in an encrypted form, which is great for security but also means that Preview is the only program that can access them. Even though an inserted signature is resizable and can be moved around in the given PDF document, you cannot copy it or a selection that contains it from Preview to another program. One solution to this is to simply scan your signature in and save it as an image, but this requires you have a scanner handy.

However, there is a workaround you can use that will allow you to capture any signature from Preview and save it as an image file with proper transparencies that you can use in other applications. First be sure you have a signature captured and stored in Preview, which can be done by following the, then perform the following steps: • Open a text editor such as TextEdit, Pages, or Word, and create a new blank document.

• Press Command-P to print the blank document and choose 'Open PDF in Preview' from the small PDF menu in the lower left. Printing a blank document to Preview as a PDF can be done in the PDF menu. Screenshot by Topher Kessler/CNET • Enable Preview's Edit toolbar (press Shift-Command-A), and use the Signature tool to add a signature to the document.

• Expand the signature size to be relatively large (the larger the better, which can also be done by zooming in on your document and expanding its window size). • Press Shift-Control-Command-4 to enter selection-screenshot mode (your mouse cursor will turn into a crosshair), and drag a selection around your signature (when you release the mouse you should hear a camera click). When you take a selection-screenshot of the signature, the mouse cursor, which above appears as an arrow, will change to look like a crosshair. Screenshot by Topher Kessler/CNET • Ensure Preview is the foremost application and press Command-N to create a new image file from the screenshot. • Enable Preview's Edit toolbar again, and select the Instant Alpha tool (it looks like a little wand). • Click the white area around the signature and drag your cursor away from where you click.

When you do this the white area will turn pink, but keep dragging until you do not see any more white around the characters of your signature. If the characters themselves show a pink hue then you have dragged too far so back off a little until they turn black again, followed by releasing the mouse button. The white area selected will turn pink, which when deleted will turn transparent.