Prot-on gives you the ability to protect and track the use of any copy of your documents.
Prot-On is free for personal use. The cost for professionals is $51.50 per year (40 €), or $1 (0,75 €) per user per month for corporate installations.
Note: Although Finder indicates no version number for this application, the developer refers to it as version 1.6.7.
Release notes were unavailable when this listing was updated.