Acrobat Sign Tool vs. Certificate-Based Digital Signatures: What is the Difference?
Question details
The user wants to understand the difference between standard electronic signatures (the Sign tool) and certificate-based digital signatures, including how to apply a certificate signature to a PDF without pre-existing fields and why documents lock after signing.
- Product
- Adobe Acrobat
- Device & OS
- not provided
- Scenario
- Applying secure signatures to PDF documents and managing document editing permissions after a signature is applied.
- Observed behavior
- The standard Sign tool applies a visual electronic signature but may unexpectedly lock editable fields upon saving, whereas the Certificates tool applies a cryptographically secure signature based on digital IDs.
Ensure you have a valid digital ID or certificate installed in your computer's Certificate Store or saved as a file before attempting to apply a certificate-based signature.
Apply a Certificate-Based Digital Signature
Use the Certificates tool to create a cryptographically secure digital signature, which protects document integrity even without an existing signature field.
A certificate-based signature offers high-level security by linking your identity to a cryptographic certificate. This ensures that any changes made to the document after it is signed will invalidate the signature.
Open your PDF in Acrobat, navigate to the 'Tools' menu, and select 'Certificates'.
Click on 'Digitally Sign' from the top toolbar.
Click and drag your mouse cursor to draw a rectangular box where you want the digital signature to appear on the document.
A dialog box will appear. Choose your existing digital ID from the Windows Certificate Store or from a file, click 'Continue', enter your password if required, and click 'Sign'.
Use the Standard Sign Tool for Visual Signatures
Utilize the Fill & Sign tool when you only need a visual representation of your signature without the need for strict cryptographic validation.
Apply Digital and Electronic Signatures using WPS PDF
WPS Office provides a highly capable PDF editor that allows you to easily insert standard visual signatures or apply secure certificate-based digital signatures, ensuring your document's integrity and authenticity.
- 1. Open the PDF File: Launch WPS Office and open your target PDF document.
- 2. Navigate to the Protect Tab: Click on the 'Protect' tab located in the top ribbon menu.
- 3. Choose the Signature Type: Click 'Sign' to add a visual electronic signature, or select 'Digital Signature' to apply a certificate-based signature.
- 4. Apply and Save: Follow the on-screen prompts to place your signature on the page, select your digital ID if applicable, and save the document.
Frequently Asked Questions
What is the main difference between an electronic signature and a digital signature?
An electronic signature (like the Acrobat Sign tool) is a visual representation of a signature, such as a typed name or drawn image. A digital signature (certificate-based) contains encrypted cryptographic data that verifies the signer's identity and ensures the document has not been altered.
Why do my PDF form fields lock after adding a standard signature?
Certain security settings or administrative configurations dictate that once a document is signed and saved, the form fields are locked to preserve the integrity of the data at the time of signing and prevent unauthorized tampering.
Can I apply a digital signature if the PDF doesn't have a signature field?
Yes. In most professional PDF editors, including Acrobat and WPS Office, you can select the digital signature tool and manually draw a signature box anywhere on the document to apply your certificate.
