How does native speaker express such meaning?

wEr   Fri Dec 09, 2005 8:55 am GMT
NO CONFIDENTIAL OR INTERNAL INFORMATION LEAVE OFFICE!
Guest   Fri Dec 09, 2005 10:24 am GMT
I think you mean "No confidential information leaves the office."
Mark   Fri Dec 09, 2005 2:41 pm GMT
CONFIDENTIAL OR PROPRIETARY INFORMATION MUST NOT LEAVE THIS OFFICE.

or

NO CONFIDENTIAL OR PROPRIETARY INFORMATION IS TO LEAVE THIS OFFICE.

or

DO NOT REMOVE CONFIDENTIAL OR PROPRIETARY INFORMATION FROM THIS OFFICE
Guest   Sat Dec 10, 2005 12:11 am GMT
NO CONFIDENTIAL OR INTERNAL INFORMATION MAY LEAVE THIS OFFICE!