Revoke the possibility to change the signature placeholder location by the end user

Which product are you using?

PDF.js Express Plus Version

Detailed description of issue
When a document is sent to a user, they have the ability to change the position of the signature after signing. Is there a way to stop that from happening.
For instance if I send a document to a user to sign at the left bottom of the document, I would prefer that the signee cannot change the position after signing the document.

Expected behaviour
This image shows the movable signature. I want to prohibit that from happening.

Does your issue happen with every document, or just one?
All the documents.

Link to document

Code snippet

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Happy new year!

You can set the ReadOnly flag to true once the annotation is created to prevent it from being moved.

  instance.Core.annotationManager.addEventListener('annotationChanged', async (annots, action) => {
    if(action === 'add') {
      annots.forEach(annot => {
        if(annot instanceof instance.Core.Annotations.FreeHandAnnotation) {
          // Make sure its a signature and not just a normal FreeHand annot
          if(annot.Subject === 'Signature') {
            annot.ReadOnly = true;


Happy New Year to you too.
Thanks a lot

1 Like

hey man. when changing readOnly = true, the delete button also gets removed hence not allowing the user to change signature. We do want them to be able to edit the signature just not the position