I could'n't find clear info anywhere or confirmation but I noticed that all documents signed with the FILL & SIGN feature of Adobe Reader (Free) cannot be locked and is editable using Adobe Acrobat Pro. the same document signed using Adobe Acrobat Pro will be locked automatically with no editing, changes to signature allowed. why is this obvious downside of using Adobe Reader (Free) not more publicised ? In fact, there is even a pop-up stating the signature will not be editable BUT that is clearly not true if signed with Adobe Reader (free)