Use third-party storage

Is it possible to create a macro to add a marker to SW files (Part, assy, drw) using the third party storage area to use as a watermark? 

The idea is to add a "mark" like a two number code to a set of files to prevent plagiarism, and avoid students from turning supplied (SW) textbook files as their own, or verify authenticity. The second part would require a macro that can scan a folder and report if the files checked have the watermark or not. 

I was trying to use the file VersionHistory, problem with that is, if a template has been recycled, it will have a history of past versions too, potentially giving false results.

Any help will be really appreciated. 

Thanks.

SolidworksApi/macros