Usually, I password-protect my PDF files in order to prevent other co-workers from accessing the documents. It happened to me to forget the passwords several times. That was when A-PDF Restrictions Remover came in handy.
Once installed on your PC, this small application will integrate in Windows Explorer and offer you two easy ways to decrypt any protected PDF file. You can either remove the restrictions from the PDF files or you can opt for the Remove Restrictions & Save as option.
My guess is that the second approach might prove to be of good use when you wish to decrypt a PDF file without leaving traces to the owner.
A useful advantage of using this restriction remover is that you can help with the decryption process (increase the decryption speed) by adding possible passwords into the Password Pool. This way, you will decrease the time spent waiting for the program to decrypt the PDF file.
To be honest, I found this application very helpful as it managed to remove any restriction from my PDF files in a minimum time. However, the program lacked other types of attacks and decryption customizations, it's a significant drawback for most advanced users.