How to Prevent Users from Signing a PDF Form in Acrobat Mobile
Question details
The user wants to prevent mobile users from adding freeform signatures to a PDF form while still allowing them to fill, comment, save, and print.
- Product
- Adobe Acrobat Pro DC
- Device & OS
- not provided
- Scenario
- Distributing a fillable PDF form and restricting the ability to sign it on mobile devices.
- Observed behavior
- Mobile users can still add freeform signatures using Acrobat Reader Mobile even after the dedicated signature fields have been removed from the form.
Ensure you have the owner password or full editing rights to the PDF document, as adjusting permission settings requires administrative access to the file's security policies.
Apply a Permission Password to Restrict Changes
Use PDF security settings to apply a permissions password that restricts signing and editing while allowing form filling.
Simply removing signature fields does not disable the freeform 'Fill & Sign' tools in Acrobat Mobile. To completely block signing, you must enforce security restrictions at the document level by adding an owner password.
Open the PDF in Acrobat Pro DC, navigate to the 'Tools' pane, and select 'Protect'.
Click on 'Advanced Options' in the top toolbar and choose 'Encrypt with Password' from the dropdown menu.
Under the Permissions section, check the box labeled 'Restrict editing and printing of the document'.
Set an owner password. Under the 'Changes Allowed' dropdown menu, select 'Filling in form fields' or 'Commenting, filling in form fields, and signing existing signature fields'. Since there are no signature fields, users will be unable to sign.
Click 'OK' to apply the security settings, save the document, and open it in Acrobat Reader Mobile to verify that the freeform signature tool is disabled.
Easily Manage PDF Permissions with WPS Office
WPS Office provides a comprehensive PDF editor that allows you to easily set permission passwords, restrict editing, and prevent unauthorized signatures or annotations. It is fully compatible with standard PDF security protocols.
- 1. Open the PDF: Launch WPS Office and open your PDF form.
- 2. Navigate to Protect: Go to the 'Protect' tab on the top ribbon and click on 'Encrypt'.
- 3. Set editing restrictions: Check the box for 'Set password to restrict editing and extracting'.
- 4. Apply permissions: Enter a secure permission password. In the permissions dropdown, select to allow only 'Filling in form fields' to prevent freeform signing.
- 5. Confirm and save: Click 'Confirm' and save the file to finalize your document security settings.
Frequently Asked Questions
Why can users still sign my PDF if I deleted the signature field?
Standard PDF readers often include a 'Fill & Sign' or freehand drawing tool that allows users to place a signature anywhere on the document unless explicitly restricted by a document permissions password.
Can I allow form filling but block commenting?
Yes. When applying a permissions password in your PDF editor, you can choose 'Filling in form fields' as the only allowed change. This will disable commenting and freehand annotation tools.
Will permission settings work on all mobile PDF apps?
Document security settings are a standard PDF feature and are enforced by most major PDF readers, including Adobe Acrobat Reader Mobile and WPS Office. However, some unofficial or loosely regulated third-party apps might ignore these restrictions.
How do I test if my PDF is truly locked from signing?
After saving the security settings, transfer the PDF to your mobile device, open it in your target app, and attempt to use the 'Fill & Sign' or drawing tools. They should be grayed out or explicitly prompt for an owner password.
