I just completed a NIST-traceable calibration on the handheld spectrometer and received the vendor's certificate as a …
Open the PDF document you want to sign in Adobe Acrobat.
Select Tools in the upper-left and then choose Protect from the tools list.
Click Sign in the Protect toolbar.
Drag to draw the signature area on the page where you want your digital signature to appear.
In the dialog that appears, select your personal digital certificate from the list.
If prompted, enter the password for your digital certificate.
Click Sign to apply your digital signature to the document.
Choose a location to save the signed PDF and click Save.
Best practiceIf you need to sign multiple documents, consider creating a reusable signature appearance to save time.
You can customize the appearance of your digital signature by editing your signature properties before applying it.
This runs in the Acrobat app - there is no separate API for this task.
A 'Certify' signature is a special type of digital signature that can only be the first signature on a PDF. It locks the document, meaning no further changes can be made without invalidating the certification. A regular digital signature can be added to a document that already has other signatures and does not prevent further changes as strictly as a certification does.
Acrobat will not let you certify a PDF if it already has other signatures. The 'Certify' feature is designed to be the very first signature on a document. It ensures the document's original state is recorded before any other changes or signatures are added.
A Digital ID is a file on your computer or a smart card that contains your private key and public certificate. You need it because it proves your identity when you sign documents digitally. The private key signs the document, and the public certificate lets others verify that your signature is real and the document has not been changed.
Yes, if you need to apply an official company seal (an organizational seal, not a personal signature) to many PDF reports, you can automate this. Adobe offers a PDF Electronic Seal API. This API allows you to programmatically apply simple, advanced, or qualified seals, which are compliant with standards like eIDAS. You would need to provide your company's certificate credentials, the seal image, and its coordinates on the document.