Adobe Reader DC and Topaz Signature Pad

We have been using Topaz signature pads with Adobe Reader for quite some time and have tested to be sure signatures could not be altered or removed once a document was signed and saved.  With Adobe Reader DC and an update that took place with this product, a user who did not sign the document has the ability to remove the signature.  I am wondering if anyone else has experienced this, and if there is a fix or patch that would stop the signature from being able to be removed.