Hi Martin,

> I just wondered if there was a part of the file header that could be encrypted
> and thus be hidden from prying eyes.

There's currently no mechanism in the 3DM file format for encrypting that particular header information, for a major change in the 3DM format itself you'd probably want to ask the Rhino guys about making any changes in that area, they're the ones that make the 3DM file toolkit for reading and writing 3DM files.

It is possible to put in custom chunks of application or plug-in specific data into 3DM files, so it could be possible to store encrypted information into the file that way, but it would be separate from the standard author header field and no other programs that read 3DM files would know how to do anything with that information and would just skip it...

- Michael