If you don't want anyone to steal or add to the classified contents in your PDF files then you need to adequately protect them. There are several reasons why you need to make sure that sensitive data in PDF files is protected. But at the same time, since the PDF format is a commonly shared document, it must be easily accessible to your users or those who read and review them. In the absence of PDF file security, you may be faced with severe consequences of a data breach. Hence, locking PDF files with right document security solution can effectively keep sensitive information within the files secured.